The implementation of New York City secondary-level transitional classes in English as a second language (ESL) is evaluated. The classes are designed to improve the listening, speaking, reading, and writing skills in English necessary for success in mainstream classes. This evaluation, based on data gathered via site visits, interviews, and an examination of curriculum materials, focused on staffing and staff training, student selection and programming, curriculum development, and classroom implementation issues. The classes were found to be diverse in terms of teacher background, student placement and programming, and instructional focus. Based on the evaluation findings, it is recommended that wherever possible, ESL transitional students should be programmed for a corresponding credit-bearing English class and that the ESL program should encourage greater articulation between teachers of the two class types. (MSE)