To understand the relationship between induction policies, programs, and practices, we conducted case studies of three long-standing induction programs. Drawing on interviews, observations, and policy documents, we asked the following: (a) What policy tools operate in these contexts, and how do they effect local induction practices? (b) What can we learn about the relationship between induction policy and practice, including its influence on mentors and work? Our analysis finds that how the problem of induction is defined shapes the nature and duration of support offered and the programmatic tools and resources provided. Our analysis further shows that mentoring emerged the favored policy instrument, although provisions for mentor training varied considerably. To support the kind of teaching demanded by today's reforms, beginning teachers will need mentors who are skilled in helping them learn in and from practice. Consequently, induction policy will need to focus attention equally on new teachers and their mentors. (Contains 10 notes and 3 tables.)