This CD-ROM collects 64 case studies, each of which raises an important and difficult ethical issue connected with planning, reviewing, or conducting health-related research. The purpose is to contribute to thoughtful analysis of these issues by researchers and members of research ethics committees (RECs), known in some places as ethical review committees or institutional review boards, particularly those involved with studies that are conducted or sponsored internationally.This collection is envisioned principally as a tool to aid educational programs, from short workshops on research ethics to in-service learning for scientists and REC members, to formal degree or certificate courses. In such settings, instructors will typically select a number of case studies that will be distributed to the participants to provoke and focus discussion. (To assist those using these case studies in their classrooms and workshops, a teaching guide has been included.) Individuals who want to stimulate their own thinking about research ethics or to become more familiar with a range of real-world dilemmas in international health research, especially in developing countries, will also benefit from this CD-ROM.