The first copies of Bill VanPatten's new text, From Input to Output: A Teacher's Guide to Second Language Acquisition (McGraw-Hill), were churned out at the plant in the final days of 2002 and began arriving via U.S. mail on January 2nd, 2003. This 114-page book is written with the purpose of making current SLA theory "comprehensible" to teachers in training as well as non-academic readers. I was able to finish reading the book in about seven hours, over the course of several sittings, but then again I spent a lot of time reflecting on the 40 different "Pause to Consider" sections which Dr. VanPatten has inserted at crucial junctures in the text.

From Input to Output has the potential to impact a new generation of ESL/EFL practitioners as deeply as Stephen Krashen and Tracy Terrell's The Natural Approach influenced those of us starting our ESL careers when it appeared in 1983. Krashen and Terrell's siren song indirectly contributed to the development of a breach between ESL teaching and formal linguistics; VanPatten has effectively reunited linguistic theory and language teaching by explaining what SLA researchers now understand about the once vague notion of "comprehensible input."

First, I'd like to point out three editing errors in the text. On page 53, about midway through the second paragraph, "participle" is misspelled. On page 72, in the last complete paragraph, the sentence "The latter is an effortful process" should have used either "former" or "effortless" in order to make sense. On page 96, in the parenthetical remark about midway through the second complete paragraph, the main verb "be" was inadvertently omitted.

VanPatten also does not quite successfully achieve a clear explanation of what syntactic "parameter resetting" is. He could have borrowed analagous terminology from the field of electronics in order to make his meaning clearer, or he could have incorporated the phrase "fixed range" and utilized more insights from the 1995 volume of the Cornell Working Papers, where "Input and Parameter Resetting in Second Language Acquisition," by Theresa Antes, Christine Moritz, and Regina Roebuck, appeared.

Bill VanPatten has, nonetheless, written a pivotal text which new as well as experienced ESL teachers are going to use to inform their choices of approaches, methods and materials. The chapter devoted to input itself is one of the most eloquent explanations you will find anywhere. VanPatten's main point is that input which is useful for language acquisition must be communicative, which means the purpose is communication and the focus is on meaning. Another key concept explained by VanPatten is "intake," which is the amount of input the learner can process within his or her "working memory." This chapter will be suggestive of many implications for how ESL and other language teachers craft the tasks which students must perform.

Throughout this insightful new textbook, VanPatten continually reiterates his strong belief that learning a language is different in several important ways from general learning of knowledge. For one thing, he says, most other learning is done through the use of language. "Language acquisition is different from any other kind of learning," says VanPatten. "A belief that most theorists and researchers in SLA share is that learning a second language involves processes and parts of the brain that are different from those used to learn other things." He goes on to ask, "If language is unique to humans, is it possible that the brain has evolved in a way that treats language separately from other human cognitive abilities?"

The central chapter in From Input to Output is about how language learners develop an implicit system of lexical, syntactic and pragmatic networks which is continuously adapting new elements and restructuring itself as it responds to new comprehensible input. According to VanPatten, explicit knowledge about a new language "can play only a supporting or ancillary role," perhaps helping learners to process input better. He compares explicit knowledge to crutches for someone with a broken leg. "In SLA, explicit knowledge may be used as a 'crutch' under certain conditions while the processes used to develop a rule in the implicit system have their chance to work," VanPatten explains.

In the chapter on output, VanPatten describes the mechanisms involved when a language learner unconsciously accesses his or her implicit system of networks (or more deliberately accesses explicit knowledge about the new language) in order to engage in communication using the L2. "Access" is defined as "activating the lexical items and grammatical forms necessary to express particular meanings." The second half of output, according to VanPatten, are "production strategies," which tend to be based on the learner's L1 early in his or her language learning experience and on the developing L2 system as language acquisition progresses.

VanPatten also touches on a relatively new area of SLA research, regarding the potential role of the learner's output in the language acquisition process. He does not believe that output plays the same sort of role as input in the second language acquisition process. However, he does think output can make a different indirectly because of the way it is involved in "negotiation of meaning," prompting another participant in the communication event to contribute input which adjusts syntax or otherwise clarifies meaning. "Making output may push [learners] to be better processors of input, something they might not do otherwise," explains VanPatten. "In this case, output may be necessary for continued growth."

The design of Bill VanPatten's new book seems well-suited to a variety of teacher-education learning styles. He follows his explication of comprehensible input, the implicit L2 system, and output strategie, with a chapter of FAQs (Frequently Asked Questions). Here are the questions which VanPatten answers thoughtfully and clearly, and in the process underscores the main themes of the entire text.