This casebook, developed in collaboration with 22 mentor teachers in the Los Angeles (California) Unified School District, provides illustrative vignettes, written by the mentor teachers themselves, of their work with first-year teachers. The vignettes describe the circumstances of each event, its consequences, and the ongoing thoughts and feelings of the participants. All the vignettes are grouped by the principle illustrated or questions raised, and brief analytical commentaries by the editors accompany each case grouping. After an introductory explanation of the methodology, the vignettes in chapter 2 focus on the process of mentoring: establishing the working relationship, individual consultation, observing and coaching, and modeling. Chapter 3 turns to aspects of the relationship between mentors and principals, with vignettes grouped around issues such as confidentiality and evaluation, the appropriate match between the two roles, and continuity of support. Chapter 4 addresses issues affecting the life of a mentor: novice teachers and novice mentors, rewards, frustrations, relations with others, and friendships with other teachers. Each chapter concludes with an annotated bibliography. (TE)