Prevention programs may differ in such areas as the occupation of the trainer, the age of children served, the length of training, the terms used to describe the prevention content, and the curriculum materials used. However, they generally rest on a common set of prevention concepts relating to acceptable and unacceptable touching, control of access to one's body, and assertive ways to respond to abuse. Research about the impacts of these programs has encountered several methodological issues, including the choice of dependent variables, ways to test the acquisition of skills, ways to measure unintended effects like fear, the timing of the measurements, and the research design. Nevertheless, evaluation efforts already completed have addressed many questions about the effects of prevention programs, and knowledge about prevention is likely to expand greatly in the immediate future. Cooperative efforts between prevention evaluators and researchers will aid this effort. 11 references.