There is a difference between learning a second language and learning a second dialect; the English as a second language (ESL) program should be limited to teaching English to students who do not already know English. Although there are not enough ESL programs, there is also a problem that some students are receiving ESL instruction even though they may actually need some other type of program. The main objective of ESL instruction is to have the student internalize the generative rules or deep structure of English as soon as possible. Even though his English differs widely from cultivated usage or is heavily influenced by borrowing from another language, the student who already knows the underlying system of English will only have to learn to make changes in the surface structure, a different task from learning the generative rules. Teachers must exercise extreme caution in determining which type of language instruction a particular student needs; background, personality, and classroom situation must all be considered. (VM)