A discussion of research goals notes that the broad goal of psychotherapeutic research is to help in the clarification of clinical concepts. It should advance understanding of psychopathology, so that more appropriate hypotheses can be developed in clinical work and for further research. The specific goal of a research project will depend on the questions being asked and the type of psychotherapy involved. An overview of research methods considers single-case and small-sample designs and group comparison studies. The latter discussion addresses the randomized controlled trial, attrition, statistical significance, statistical power, and clinical significance. In addressing the implementation of research, the author advises that the essential factor for research is the quality of the design of the methodology, which makes the results meaningful whether or not they attain statistical significance. Suggestions are offered when the aim of the research is to investigate the internal world of the offender or to conduct outcome studies. A section on "critical issues for forensic psychotherapy research" discusses ethical issues, the reliability of information provided by offenders, the effect of the setting, the population of offenders, and follow-up. The paper concludes with a discussion of new directions for future research.