This unique book explains the theory behind peer-led team learning, offers suggestions for successful implementation (including how to write effective group problems and how to train peer leaders), discusses how to evaluate the success of the program, and answers frequently asked questions. It is designed as a workbook, to be used as the central focus of activity in a PLTL Workshop in organic chemistry. It is not a drill book, nor is it a self-contained guided inquiry book. As with the Workshops themselves, this book is intended to be a companion to a textbook in a lecture course. The Workshop problems are challenging, and readers need to prepare for them by studying the book, the lectures, and by working the end-of-chapter problems ahead of Workshop time.