The Mentor Teacher Program in the state of California is designed to retain capable teachers by expanding their rewards and opportunities. This report focuses on the character and quality of mentoring in an alternate route program sponsored by a large urban school district. A 30-hour required training course for mentors introduces them to their new role and provides skills and strategies they can use in their work. Three cases of mentoring, all involving English teachers at the secondary level are described, analyzed, and appraised. The influence of mentor training on mentor's practice is traced and the problematic consequences of that training are pointed out. To learn more about what mentor teachers do when working with beginning teachers three sources of data were examined: (1) a training manual; (2) transcripts of conferences between mentor teachers and teacher trainees; and (3) interviews with mentors about those sessions. Results suggest that the traditional supervision of student teachers is more similar to than different from the mentoring of alternate route candidates; and this kind of mentoring may not offer any improvement over the more traditional methods of teacher supervision that it is intended to replace. (Contains 15 selected references.) (LL)