An introduction to the work of Stephen Krashen

This page contains an introduction to the work of Stephen Krashen, probably the most influential researcher in the field of second language acquisition.


This article contains a brief synopsis of the work of Stephen Krashen, Emeritus Professor of Linguistics and Education at the University of Southern California. It focuses on his research and insights in the fields listed above.

Each synopsis is followed by comments and a summary of implications for mainstream teachers of ESL students. Teachers who are interested in further information about the various issues can click [More] at the end of each section. Or click → to expand all further information at the outset.

Note: The page was written for mainstream teachers in advance of a two-day workshop held by Professor Krashen at Frankfurt International School.

Second language learning

Krashen believes that there is no fundamental difference between the way we acquire our first language and our subsequent languages. He claims that humans have an innate ability that guides the language learning process.

Infants learn their mother tongue simply by listening attentively to spoken language that is (made) meaningful to them. Foreign languages are acquired in the same way.


More on innate language learning

The claim that humans possess an innate language learning ability stems from Chomsky (1965), who rejected Skinner's (1957) behaviourist theory that language learning is habit formation through stimulus and response. Chomsky called the special inborn language capability the Language Acquisition Device (LAD).

From this he developed the theory that all languages share an underlying system named Universal Grammar. The hypothesis that the ability to learn language is innate has been restated more recently by linguist Steven Pinker who claims that this ability is "hard-wired in the genes".

Chomsky and Pinker are nativists. Their theories are opposed by contemporary empiricists such as Sampson (2005), who reiterate Skinner's claim that language develops in response to environmental influences.

Other linguists and cognitive scientists, such as O'Grady (2005), agree that humans possess significant innate capabilities. However, they suggest that language learning depends on general cognitive faculties rather than on a specific language acquisition mechanism.

Krashen synthesizes his theories of second/foreign language learning in what is usually referred to as the Monitor Model. This model has five components:

1. The Acquisition-Learning Hypothesis

There are two ways of developing language proficiency: by acquisition and by learning.

Acquisition is a sub-conscious process, as in the case of a child learning its own language or an adult 'picking up' a second language simply by living and working in a foreign country.

Learning is the conscious process of developing a foreign language through language lessons and a focus on the grammatical features of that language.


More on the Acquisition-Learning Hypothesis

According to Krashen learned language cannot be turned into acquisition. It is pointless spending a lot of time learning grammar rules, since this will not help us become better users of the language in authentic situations.

At most, the knowledge we gain about the language will help us in direct tests of that knowledge or in situations when we have time to self-correct, as in the editing of a piece of writing.

2. The Natural Order Hypothesis

Language is acquired in a predictable order by all learners. This order does not depend on the apparent simplicity or complexity of the grammatical features involved.

The natural order of acquisition cannot be influenced by direct teaching of features that the learner is not yet ready to acquire.


More on the Natural Order Hypothesis

It is claimed that the natural order of acquisition is very similar for a native-English child learning its own language and for an adult learning English as a foreign language.

For example, the -ing form (present continuous: he is eating) will be acquired early on and almost certainly before the -s inflection in the third person present simple (she likes, he eats , etc.)

As Krashen points out, much of the frustration experienced by teachers and their students in grammar lessons results from the attempt to inculcate a grammatical form which the learner is not yet ready to acquire.

3. The Monitor Hypothesis

We are able to use what we have learned (in Krashen's sense) about the rules of a language in monitoring (or self-correcting) our language output. Clearly, this is possible in the correction of written work. It is much more difficult when engaging in regular talk.


More on the Monitor Hypothesis

Krashen states that it is often difficult to use the monitor correctly since the rules of a language can be extremely complex. Two examples from English are the rules about the articles (a/the) and the future "tense".

Even assuming the learner has a good knowledge of the rule in question, it is difficult to focus on grammar while simultaneously attempting to convey meaning (and possibly feeling). Most normal conversation simply does not provide enough time to do so.

The cartoon linked to at the foot of the page Final thoughts about grammar shows when not to use the monitor. In Stevick's terminology, JM in the cartoon is suffering from lathophobic aphasia, an "unwillingness to speak for fear of making a mistake". (See Krashen at: Second Language Acquisition and Second Language Learning [Page 4].)

4. The Input Hypothesis

We acquire language in one way only: when we are exposed to input (written or spoken language) that is comprehensible to us. Comprehensible input is the necessary but also sufficient condition for language acquisition to take place. It requires no effort on the part of the learner.


More on the Input Hypothesis

Krashen now refers to this as the Comprehension Hypothesis. It states that learners acquire language when they are exposed to input at i+1, where i is the current state or stage of language proficiency.

Learners use their existing acquired linguistic competence together with their general world knowledge to make sense of the messages they receive in language just beyond where they currently are (the +1). Given comprehensible input at i+1, acquisition will take place effortlessly and involuntarily.

This theory has clear implications for language teachers. Namely, that their language instruction should be full of rich input (both spoken and written language) that is roughly tuned at the appropriate level for the learners in the class.


5. The Affective Filter Hypothesis

Comprehensible input will not result in language acquisition if that input is filtered out before it can reach the brain's language processing faculties. The filtering may occur because of anxiety, poor self-esteem or low motivation.


More on the Affective Filter Hypothesis

Learners with a low affective filter (i.e. low stress or anxiety) will not only be efficient language acquirers of the comprehensible input they receive. They are also more likely to interact with others, unembarrassed by making mistakes for example, and thus increase the amount of that input.


Krashen's Monitor Model has attracted enormous attention from psychologists, fellow linguists and educators. His theories have been criticised for a perceived lack of scientific rigour and for his downplaying of the importance of language output and grammar instruction.

Nevertheless, @@ the Monitor Model has been extremely influential in language teaching pedagogy. ~~It is the theoretical basis for ESL instruction at Frankfurt International School and numerous other schools world-wide.


More comments on Krashen's theory of second language acquisition

Early responses to Krashen's theory (Gregg, 1984; McLaughlin, 1987) based their critique in the claim that Krashen's constructs (such as the learning/acquisition distinction) are not empirically verifiable and hence not falsifiable.

However, the concept of falsifiability, as the means for distinguishing science from non-science (Popper, 1959), has itself come in for considerable criticism, (e.g., Lakatos, 1970; Schumann, 1993).

Feyerabend (1981) contends that adhering to strict empiricist methodologies can inhibit scientific progress. Indeed, it is disputed whether linguistics can or should be regarded as a science (see Harris, 1993).

Teachers, of course, are concerned with the practical worth of a particular theory and are generally oblivious or impervious to such ivory-tower discussions. Whether or not Krashen's theories of language acquisition meet certain scientific criteria, it is indisputable that they have been widely and successfully applied in the classroom.

Subsequent critiques of Krashen have focused more on the pedagogical implications of his theories. For example, Krashen's claim that comprehensible input is a sufficient condition for language acquisition. Critics, e.g., Swain (1985), counter that the production of language (output) is a necessary condition for language development.

A further criticism of Krashen's theories is levelled at his repudiation of grammar instruction. Critics claim that some kind of direct focus on grammar is both beneficial and necessary - see Long (1998).

Krashen (2003), after a comprehensive analysis of the research data in these two areas, concludes that neither learner output nor grammar focus have any direct influence on acquisition. He states that his hypotheses

"...have not only survived well over the years but have also proven to be useful in other areas of language education. So far, research results remain consistent with these hypotheses and there is no counterevidence."

Following are two small pieces of anecdotal data from Frankfurt International School in support of Krashen's theory of comprehensible input:

Anecdote 1: We were joined a while ago by an Italian boy who had a little German but no English. He did not want to be here and had to be dragged in (literally) by his parents on the first day. He refused to speak any English at all (even in ESL class) for his first 4-5 months at the school.

However, after he overcame his initial negativity and high anxiety (or, in Krashen's terms, after his affective filter came down), he listened attentively in class and spoke German when he needed to communicate.

Shortly after Christmas he decided that he was ready to speak English and he did so with an accuracy and fluency some way beyond the other students in the class.

Admittedly, his classmates were mostly Asians whose native languages are much further from English than Italian is. It also helped that the boy had already had the experience of learning a foreign language.

Anecdote 2: A year or so later a grade 7 Hungarian student joined FIS with no English at all - she did not even know all the numbers to twenty. Although she was the only Hungarian-speaker in the school, she possessed an outgoing personality and a positive approach.

She soon had a group of friends who helped her both in and out of class to cope with the social and academic demands of school life. Her English developed very fast and towards the end of her first year, she expressed her irritation at the postponement of a test: "If I'd known, I wouldn't have studied so hard!"

ESL teachers will tell you that that's pretty impressive!

More on the current state of SLA

The field of linguistics has expanded rapidly in the last 4-5 decades, and SLA research is currently divided into two camps: the sociolinguists and the psycholinguists.

Sociolinguists are concerned with how language acquisition occurs in the various situations in which the learner finds him- or herself.

Psycholinguists on the other hand are more interested in the cognitive processes that take place when an individual learns a new language (see Ellis, 2009).

Krashen's Monitor Model is just one (albeit the most renowned) of a multitude of SLA theories propounded by both socio- and psycholinguists. There is currently a rather acrimonious debate over whether the proliferation of theories is inevitable and desirable (e.g., Schumann, 1993) or undesirable and a cull is overdue (Long, 2006).

Implications for mainstream teachers

Firstly, if teachers make their classroom instruction comprehensible, then not only will the ESL students learn the subject content but they will be acquiring English at the same time. All teachers of non-native English students should regard themselves as teachers of language too.

Secondly, @@@ ESL students are often anxious in mainstream classes. Teachers should seek ways to reduce the students' affective filter in order that they can profit from the comprehensible input they receive. ~~~

Here are four pages from elsewhere on this website with information about how to provide comprehensible input and lower the affective filter:

Free voluntary reading

Free voluntary reading (FVR) is the reading of any book (newspaper, magazine or comic) that students have chosen for themselves and is not subject to follow-up work such as comprehension questions or a summary.

@Krashen (2003) makes the claim that free voluntary reading may be the most powerful educational tool in language education. It serves to increase literacy and to develop vocabulary.~

Extensive voluntary reading provides non-native students with large doses of comprehensible input with a low affective filter. Thus it is a major factor in their general language acquisition.


More on free voluntary reading

Krashen (2004) expands on his claim in his book The Power of Reading. His own and others' research has led him to the following conclusions:

  • Students who read more do better on a wide variety of tests.
  • Reading is the most significant factor in the development of vocabulary.
  • Reading is the major factor in the development of writing competence.
  • Students who read extensively have a greater general knowledge.
  • Self-selected reading is extremely enjoyable and probably the most popular means of achieving of what Csikszentmihalyi (1991) calls flow, the psychology of optimal experience.

Here is a useful online summary of Krashen's recent work on FVR.

Krashen is a passionate advocate for libraries and was asked to submit a report on the issue to the Obama-Biden Education Policy Working Group. In the report Krashen (2008) points out the correlation between library provision and student reading achievement. He states that libraries are even more important for children growing up without books at home:

"My conclusions are simple. When children read for pleasure, when they get hooked on books, they acquire involuntarily and without conscious effort, nearly all of the so-called language skills many people are so concerned about.

They will become adequate readers, acquire a large vocabulary, develop the ability to understand and use complex grammatical constructions, develop a good writing style and become good (but not necessarily) perfect spellers." (2004)


Krashen's research has led many schools to implement in-class reading programmes such as Sustained Silent Reading (SSR). Investigations conducted by the US National Reading Panel (2000) did not find clear evidence that these programmes made students better readers or encouraged them to read more.

Some educators (see Klump, 2007) believe that SSR is not the most productive use of instructional time. Krashen's response is that the NRP's research was flawed and that SSR does indeed result in better readers and more reading.


More comments on free voluntary reading

ESL teachers at Frankfurt International School have students read for about 10 minutes in class on a regular basis. We have no objective data showing how effective this is in terms of students becoming better or more avid readers.

However almost without exception, students look forward to their silent reading. They are often so inundated with other work that they have no time to read for pleasure at home.

Students appreciate the short amount of quiet time in what is otherwise a very hectic, demanding school day. And their language acquisition is almost certainly accelerated by the comprehensible input they receive.

Implications for mainstream teachers

It is desirable that students develop the habit of regular reading in each discipline, even if teachers prefer not to use instructional time to enable this.

They may wish, therefore, to assign self-selected reading as occasional homework and have students report back on anything they feel worthy of sharing with the rest of the class. This is particularly useful if the students are encouraged to read about the topic in their mother tongue.

Teachers can collaborate with the librarian to stock the library and the classrooms with interesting materials. Students can be given lists of recommended websites.


Free voluntary reading - more implications for mainstream teachers

While it is necessary to use direct measures to encourage or require student reading, it is also important to expose students to subliminal messages that reading is highly enjoyable and a very effective way to become an interesting and knowledgeable person.

These subliminal messages might include a prominent bulletin board featuring a book of the week with a review written by a student or teacher, or the results of survey in which teachers and students list their favourite books. Every classroom could be equipped with a small rack of books and magazines making it easy for students to browse and borrow.

Teachers could be often seen walking along the corridor immersed in a book. They could comment from time to time in class on something they have read in the newspaper or a magazine.

Reading proficiency correlates so highly with academic success that every effort should be made to create a reading culture in the school and in the classroom. To emphasise the point, it is worth quoting a long passage from Pretorius (2000):

Research findings in applied linguistics and reading research consistently show a strong correlation between reading proficiency and academic success at all ages, from the primary school right through to university level: students who read a lot and who understand what they read usually attain good grades.

In fact, the relationship between reading and learning begins even earlier in the pre-primary school years - children who are exposed to storybook reading before they go to school tend to have larger vocabularies, greater general knowledge and better conceptual development than their peers, and in addition, they learn to read and write more easily and quickly... .

The correlation between reading proficiency and academic performance obtains for both those who study through their first language (L1 students) and for those who do not (L2 students). In fact, several teachers and researchers argue that reading is probably the most important skill for L2 students in academic or learning contexts... .

Gallagher (2009) has some useful suggestions on how to broaden students' background knowledge by assigning article-of-the week readings.

Bilingual education

Recent decades have seen a dramatic increase in the number of non-native speakers of English in the classrooms of Great Britain, the USA and other English-speaking countries.

Educators in this period have been debating how best to meet the special needs of these students. In broad terms there are two opposing approaches:

  • maximize the learner's exposure to English
  • provide instruction in the mother tongue as well as in English.

Krashen is a strong advocate of the second approach, which finds its implementation in one of the forms of bilingual education.


More on bilingual education

Immersion or English-only are common names for educational approaches that are based in the simple, and somewhat intuitive belief, that 'the more English, the better'. The mother-tongue has no role to play.

Bilingual models, on the other hand, are founded on the hypothesis that academic proficiency (knowledge, understanding, skills, etc.) acquired in the native language are available to the student when learning takes place in English (see Cummins, 2000).

Furthermore, this academic proficiency facilitates the acquisition of English because it helps to make what students hear and read more comprehensible to them. Proponents of bilingual programmes claim that much immersion or English-only instruction is incomprehensible to non-native speakers, who therefore learn neither English nor subject content.

There is a large variety of bilingual educational models. The one that research (e.g. Collier & Thomas, 2004) suggests to be the most effective is two-way bilingual instruction.

A typical two-way bilingual class consists of approximately equal numbers of native (or very proficient) speakers of English and speakers of a different native language (e.g. Spanish). The class remains together for all of their lessons, some of which are in English and the remaining ones in Spanish.

Krashen (with Crawford, 2007) has written a useful introduction to the issues and controversies surrounding bilingual education in the United States. Here are two articles on his website:

Cummins is another major proponent of bilingualism. He has written extensively not only about its pedagogical advantages but also about its cultural, cognitive and political benefits.

See his book Bilingualism in education: aspects of theory, research, and practice , co-authored with M. Swain.


Bilingual educational is a highly contentious issue, particularly in the USA. The strong arguments from research that mother-tongue support for non-native English students is beneficial for both their English language and their academic development have not been found convincing by much of the general public.

Politicians have seen the issue as a way to gain voter popularity. Indeed, the whole question has become subsumed in volatile side issues such as race, immigration and poverty. The proponents of bilingual education, Krashen included, have been subject to intemperate personal attacks.


More comments on bilingual education

The most protracted debate about the efficacy of bilingual education has taken place in California, where private initiatives pass into law if they gain majority support in a referendum.

Under the auspices of the 1968 Bilingual Education Act many Californian schools offered bilingual programmes for their increasing Hispanic populations. Then in 1998 the state's voters approved Proposition 227, a bill sponsored by Republican Ron Unz (2001), which virtually banned bilingual education at the expense of English-only models (in most cases one-year structured English immersion classes).

The majority support (61%) for the proposition reflected the public's resistance to language diversity - the assimilative metaphor of the melting pot is deeply engrained in American consciousness. Krashen (2007) claims that voters were mislead by politicians and by media treatment of the issue.

Voters were led to believe in the mutual exclusivity of learning English effectively and being educated bilingually. Krashen admits that educators and academics were ineffective in helping the public to a better understanding of what they were voting on.

In 2002 the Bush administration replaced the 1968 Bilingual Education Act with the English Proficiency Act, informally known as No Child Left Behind (NCLB). In essence, the law reflects the belief that setting measurable goals and assessing regularly via standardized tests whether these goals are being met is the basis of effective education.

It applies sanctions (including withdrawal of funding) and other "corrective action" to schools whose students do not meet the yearly progress targets. The consequence of NCLB has been that many schools country-wide have dropped bilingual classes and adopted English-only programmes with a view to preparing students for these high-stake tests.

Unsurprisingly, there is dispute as to the success of NCLB. Supporters have pointed, for example, to improved test scores in a number of areas. Opponents, including Krashen (e.g., 2009), counter that the ostensible improvements are due to a selective interpretation of the results, and they decry the narrowing of education associated with teaching to the test. He states:

There is no evidence that more testing leads to better achievement; in fact, there is tremendous evidence that it has the opposite effect, converting instruction into test-prep rather than real learning. (2009)

Krashen also objects to standardized tests because of their expense. He argues that schools should stock their libraries with interesting materials rather than spend money on costly tests that tell teachers little they do not already know about their students.

Implications for mainstream teachers

The dispute about optimal programme support for ESL students does not have a direct impact on mainstream teachers. However, research in the fields of second language acquisition and bilingual education has taught us that the first language is a very important tool both in acquiring the second language and in learning content/skills in that second language.

The major reason for this is that judicious use of the mother-tongue serves to make English input comprehensible.


Bilingual education - more implications for mainstream teachers

A simple example of how the mother tongue can be used to make input comprehensible is the student who reads about the storming of the Bastille in her native language before listening to a lecture on the topic in class or reading about it in her history textbook. It is helpful if teachers regularly encourage students to make use of this strategy.

Cummins (2001) is the researcher most closely associated with the theory that use of the mother tongue can support second language acquisition and the learning of subject content.

Cummins postulates the existence of a common underlying proficiency (CUP), so that knowledge, understanding and skills acquired in language 1 are available for use in language 2. As Cummins states:

Conceptual knowledge developed in one language helps to make input in the other language comprehensible.

For example, if a child learns the concepts of justice or honesty in her own language, all she has to do is acquire the label for these terms in English. She has a far more difficult task, however, if she has to acquire both the label and the concept in her second language.

As we saw above, Krashen states that anxiety is a filter of comprehensible input. ESL students who know that they will be allowed or encouraged to use their mother tongue are likely to be less anxious than those who know that its use is prohibited. They will thus be generally more receptive to the English they hear.

A typical example of judicious use of the mother tongue would be for a more proficient Japanese learner of English to explain quickly in Japanese to a less proficient peer what the teacher has told the class to do.

Here is an article on the issue from Parents section of this website: The importance of the mother tongue .

Whole Language

Krashen is a strong advocate of the whole language approach to the teaching of reading. He has written many articles in support of it. In essence, whole language proponents claim that children learn to read most enjoyably and efficiently by exposure to interesting stories that are made comprehensible to them through pictures and discussions.

This is in contrast to structured decoding programmes (usually designated phonics) in which children learn to read by sounding out the various parts of words.


More on Whole Language

Whole language is the term for a conglomeration of holistic theories of learning. The principle is that proficiency is acquired by engaging in whatever is to be learned (complex though it may be), rather than separating out the component subskills for discrete practice before putting them together again.

The whole language approach became a major educational paradigm in the latter decades of the 20th century, mainly in respect of learning to read. In recent years, however, there has been something of a backlash (often called Back to Basics).

Phonics has made a comeback, particularly in the US, where it has been facilitated by the policies enacted under the No Child Left Behind programme in 2002.


The whole language/phonics debate has become politicised and increasingly vitriolic. Constant media reports about falling literacy standards have alarmed parents, many of whom vehemently protest if they consider their child's school to have chosen the wrong approach.

The issue is further complicated by the involvement of publishing houses which stand to make large profits if school districts can be persuaded to buy their comprehensive sets of phonics-based materials. Such an entanglement of interests is rarely conducive to making the best pedagogical decisions.


More comments on Whole language

Reading proficiency, the prime focus of the whole language approach, is in many ways the primary academic skill. Children who are poor readers usually struggle badly in school.

It is no surprise, therefore that there has been such an enormous amount of research on the issue, and a similar amount of debate on the pedagogical implications of the findings.

Teachers who would like to know a little more about the main issues are recommended to follow these links:

Implications for mainstream teachers

While this debate clearly has considerable implications for teachers of young children, it has little or no direct impact on mainstream teachers at upper school level, the intended audience of this web page.

Nevertheless, teachers of older students (and parents) may wish to have a little knowledge of such a contentious pedagogical issue.

Cognitive development

Krashen (2003) claims that cognitive development, including the acquisition of concepts and facts, is more likely to occur through problem-solving than through deliberate study.

It is a confusion of cause and effect to teach facts and thinking skills in order that students may then solve real problems. Instead, it is the case, Krashen says, that learning is the result of working on real problems.

Writing that synthesizes knowledge gained from various sources, incorporates personal insights, and presents these in a structured way is an excellent example of a problem-solving activity that leads to cognitive development.


More on cognitive development

Krashen's (2003) hypothesis that we develop new cognitive structures and long-term memory by problem-solving is influenced the work of Wallas (1926) and Smith (1985).

According to Wallas, problem-solving (or creativity) involves 4 stages: preparation, incubation, illumination and verification.

The concept of cognitive development ("becoming smarter") resulting from problem-solving is exemplified in the Whole Language approach to reading. Our knowledge of phonics, spelling, sentence structure and good writing style is gained through reading and writing. It is not the cause of reading and writing ability.

Krashen (2001) develops this argument in a paper criticising the trend to more testing in schools.

Note: There is more on the influence of writing on cognitive development in the following section.


Krashen's theory of cognitive development is based in the holistic paradigm. This paradigm has at its core the belief that teaching is most effective when it engages students in authentic, complex tasks rather than discrete skill-building.

The holistic approach, which became popular in the 1960s, is now held responsible by some for what they claim to be a general decline in educational standards. This reactionary movement is often referred to as Back to Basics.


More comments on cognitive development

A common term for the purported decline in academic expectations is dumbing down. Donnelly (2007) has written a book with this title.

Krashen disputes that standards of literacy among middle-class children are in decline.

Students from well-funded schools who come from high-income families outscore all or nearly all other countries on international tests. Only our children in high poverty schools score below the international average. The US has the highest percentage of children in poverty of all industrialized countries (25%, compared to Denmark's 3%). Our educational system has been successful; the problem is poverty. (2009)

Krashen is a strong opponent, in particular, of one facet of the Back to Basics movement. Namely the teaching and regular testing of discrete facts and skills.

Chalk-face educators are more likely to favour holistic approaches than politicians, journalists, parents and some school administrators. Unfortunately, it is often the latter who shout the louder and have more influence.

Anecdotal confirmation of the hypothesis that we get smart by solving problems is provided by this webpage author's son.

In the course of playing Pokemon games by himself and with his friends he built up an enormous amount of knowledge about the hundreds of Pokemon characters, their interrelationships, weapons, strength and weaknesses, and so on.

Of course, a game is not a problem in the common sense of the word, but it falls within the scope of what Krashen means by problem-solving.

Implications for mainstream teachers

The most important implication is that teachers should seek out relevant, real (or realistic) problems for their students to solve. In other words, problems that interest the students and that naturally entail researching, thinking, discussing, reading and writing or presenting.


Cognitive development - more implications for mainstream teachers

Finding real problems for students to solve is clearly not a new concept for teachers. But they are facilitated in their task if schools have curricular models that support them.

The Structures interdisciplinary project at FIS is an excellent example of how the interdisciplinary approach can set students real and interesting problems to solve.

Curricula that have more breadth than depth often do not allow for the solving of real problems. In the effort to cover a large amount of ground there is simply no time for the four stages of creativity to take place.


Krashen's (1984) early work in this field draws the distinction between writing competence and writing performance. Competence is the largely sub-conscious, abstract knowledge of what constitutes good prose. Competence is acquired for the most part through reading.

Performance, on the other hand, refers to the conscious application of strategies or rules that have been learned and practised.

The distinction between competence and performance in writing parallels that between acquisition and learning in second language development.

In his later work Krashen (2003) investigates how writing can contribute to cognitive development. He summarizes research that shows how various writing activities, in particular note-taking and summary writing, are significant aids to learning.


More on writing

Krashen claims that writing competence, "the feel for what good writing looks like", arises through reading. Writing practice has no impact on competence. He states:

...nearly all of our educated vocabulary, our ability to write coherently, our mastery of the conventions of writing, as well as a great deal of knowledge, including "practical knowledge", comes from wide reading. It is very difficult to teach these things as discrete items, and is often, in fact, impossible, because the systems to be mastered are too complex and large. Attempts to do this will dominate the curriculum and will drive out activities that help children the most. (Krashen, 1984)

Nevertheless, the quality of the learner's written end product, a school composition for example, can indeed be influenced by practice and the grammar/usage rules that the student has learned.

Krashen devotes much attention to the writing strategies that have been found to be effective in improving writing quality. These include flexible planning, frequent revision, and postponement of editing.

Krashen states further that practice, i.e., regular writing, correlates with creativity. It is wrong to believe that ideas and inspiration must precede writing. On the contrary, these often result from regular writing and the periods of incubation in between.

When we write down ideas, the ideas become concrete. They are then more readily available for inspection and modification.


The important insight from Krashen's work is that neither competence nor performance is alone sufficient in the production of a good piece of writing. Extensive reading, regular writing practice and the acquisition of writing skills and strategies are all necessary to ensure a strong end product.


More comments on writing

Performance strategies, such as frequent revision and the delaying of editing, form part of the learner-centered approach to the development of writing ability commonly known as Process Writing.

This approach became very popular in the latter decades of the twentieth century, replacing skills and rules-based writing instruction that had formerly dominated.

Process writing, as it is practised in some schools, has come under fire recently. It has been criticised for the emphasis on process at the expense of product, and for the assumption that writing skills will be acquired intuitively.

Some critics are concerned that expository writing is neglected in favour of narrative or fictional writing. Other criticism focuses on problems with peer response, an important stage of process writing.

This site has a detailed introduction for students in how to apply the Writing process.

Implications for mainstream teachers

Students who take notes in class and make summaries learn more than those who do not. Teachers should therefore consider requiring students to have a notebook and pencil at the ready in every lesson.

ESL students can be encouraged to use their own language in noting down information and ideas. Teachers may also wish, from time to time, to have the students write a short paragraph summarizing the essential content of the lesson or section of it.

Again, in the case of ESL students this summary could be in the mother tongue.

Since reading is the essential ingredient in the development of writing competence, teachers could encourage or require self-selected reading in their subject area.


Writing - More implications for mainstream teachers

Krashen (1984) applies his theory of the affective filter to the acquisition of writing competence. Learners who are anxious or have low expectations of success are less likely to become proficient writers, regardless of the amount and quality of the reading they do.

A common problem among ESL students is failure to understand the writing task clearly, what its product should include and how it should be presented. This applies to short written responses to worksheet/textbook questions as well as to extended pieces of writing such as a lab report or composition.

Attempting to write without clarity about the outcome is an obvious cause of anxiety and, in Krashen's terms, results in the raising of the affective filter.

One simple and effective way that teachers can reduce student anxiety about completing the writing task correctly is to show them a model answer. The Smartboard is the perfect tool for briefly displaying what a good answer looks like.

Teachers could collect good responses from previous years' students for this purpose. Alternatively, teachers could occasionally write the model answers. Doing ourselves what we require the students to do for us is a useful (not to say, salutary) exercise!

Here is a page with more suggestions about how to make tasks comprehensible and achievable for ESL students.


Krashen's research and writings have inspired an enormous amount of attention over the last several decades. The thousands of research studies, scholarly articles and books based on Krashen's work are testimony to the major contribution he has made to advancing knowledge and understanding in the fields of linguistics and education.

Significant numbers of teachers across the world have based their instruction on Krashen's theories, to the benefit of the learners in their classrooms.

Further reading

There are links to the full text of two of Krashen's early books about second language acquisition as well as to numerous journal articles on Krashen's website.

This Wikipedia article about Krashen focuses mainly on his involvement in the debate about bilingual education.


Second language acquisition

Chomsky, N. (1965). Aspects of the Theory of Syntax. Massachusetts: MIT Press. 
Ellis, R. (2009). Developments in SLA Research (Monograph). Retrieved from 
Feyerabend, P. (1981). Problems of Empiricism. Philosophical Papers, 2. 
Gregg, K. (1984). Krashen’s Monitor and Occam’s Razor. Applied Linguistics, 5, 79-100. 
Harris, R. (1995). The Linguistics Wars. Oxford: Oxford University Press. 
Lakatos, I., & Musgrave, A. (1970). Falsification and the methodology of scientific research. In 
Criticism and the Growth (p. 91–196). Cambridge: Cambridge University Press.
Long, M. (1998). Focus on Form: Theory, Research and Practice. In C. Doughty & J. Williams, Focus on 
form in classroom second language acquisition. Cambridge: Cambridge University Press.
Long, M. (2006). SLA: Breaking the siege. Problems in SLA. New Jersey: Erlbaum. 
McLaughlin, B. (1987). Theories of second language learning. London: Arnold. 
O'Grady, W. (2005). How children learn language. Cambridge: Cambridge University Press. 
Pinker, S. (1994). The Language Instinct. New York: HarperCollins. 
Popper, K. (1959). The Logic of Scientific Discovery. New York: Basic Books. 
Sampson, G. (2005). The Language Instinct Debate. London: Continuum International Publishing Group. 
Schumann, J. (1993). Some problems with falsification: An illustration from SLA research. Applied 
Linguistics, 14, 295-306.
Skinner, B. (1957). Verbal Behavior. New York: Copley Publishing Group. 
Swain, M. (1985). Communicative competence: Some roles of comprehensible input and comprehensible 
output in its development. In S. Gass & C. Madden, Input in Second Language Acquisition (pp.
235-256). New York: Newbury House.

Free voluntary reading

Csíkszentmihályi, M. (1991). Flow: The Psychology of Optimal Experience. New York: HarperCollins. 
Klump, J. (2007). What the Research Says (or Doesn’t Say) About Sustained Silent Reading. 
NorthWest Education, 2(12). Retrieved from
Gallagher, K. (2009). Readicide: How schools are killing reading and what you can do about it. Portland, Maine: Stenhouse Publishers. 
Krashen, S. (2003). Explorations in Language Acquisition and Use. Portsmouth, NH: Heinemann. 
Krashen, S. (2004). The Power of reading. Portsmouth, NH: Heinemann. 
Krashen, S. (2008). The Case For Libraries and Librarians. Submitted to the Obama-Biden Education 
Policy Working Group. (The Case For Libraries and Librarians). Retrieved from
National Reading Panel. (2000). Report of the National Reading Panel. Washington: National Institute 
of Child Health and Human Development.
No Child Left Behind, Fed. Reg. (2002), 
Pretorius, E. (2000). What they can’t read will hurt them: reading and academic. Innovation, 21, 
33-41. [ ]

Bilingual education

The following link is to a National Public Radio broadcast in which Krashen debates with educators on the successes and failures of bilingual education:
Collier, V., & Thomas, W. (2004). The astounding effectiveness of dual language education for all. 
NABE Journal of Research and Practice, 2(1). Retrieved from
Crawford, J., & Krashen, S. (2007). English Learners in American Classrooms. New York: Scholastic. 
Cummins, J. (2000). Language, Power and Pedagogy: Bilingual Children in the Crossfire. Clevedon: 
Multilingual Matters.
Krashen, S. (1996). Under Attack: The Case Against Bilingual Education. Burlingame, CA: Language 
Education Associates.
Krashen, S. (2009). Does Intensive Decoding Instruction Contribute to Reading Comprehension? 
(Monograph). Retrieved from
Unz, R. (2001) California and the End of White America (Monograph).  Retrieved from 

Whole language

Flesch, R. (1986). Why Johnny Can't Read: And What You Can Do about It. New York: Harper & Row. 
Krashen, S. (1999). Three Arguments Against Whole Language & Why They Are Wrong. Portsmouth, NH: 
Smith, F. (2005). Reading Without Nonsense. New York : Teachers College Press. 

Cognitive development

Donnelly, K. (2007).  Dumbing Down. Melbourne: Hardie Grant Books. 
Krashen, S. (2001). The Testing Movement and Delayed Gratification. Educators for Urban Minorities, 
2(1), 48-50.
Krashen, S. (2003). Explorations in Language Acquisition and Use. Portsmouth, NH: Heinemann. 
Smith, F. (1985). Comprehension and Learning: A Conceptual Framework for Teachers. New York: Holt 
McDougal .
Wallas, G. (1926). The Art of Thought. London: Penguin. 


Krashen, S. (1984). Writing: Research, Theory and Applications. Oxford: Pergammon. 
Krashen, S. (2003). Explorations in Language Acquisition and Use. Portsmouth, NH: Heinemann.