Despite the recent focus on the role of dialect differences in creating learning difficulties for speakers of nonstandard dialects of English, research has tended to concentrate on difficulties related to speaking and reading, while ignoring those involved in teaching writing to these students. This paper attempts to meet the need for such studies by dealing with the role of "dialect interference" in the writing of speakers of one nonstandard dialect, Black English, here defined as the dialect "typically spoken by lower socioeconomic class Blacks and distinguished from other nonstandard dialects by a number of pronunciation and grammar features. "The paper first discusses the notion of dialect interference and how it can be applied to writing and then reports a study conducted by the authors using as their data compositions written by tenth-grade speakers of Black English. These compositions are examined in the light of certain established facts about Black English (both phonological and grammatical) to ascertain the extent to which dialect interference can be used to explain certain phenomena found in the students' writing. The authors conclude that dialect interference does indeed play a role in the writing of Black English speakers and discuss the implications of this conclusion for the composition teacher. (FWB)