In recent years, policymakers and practitioners have become aware of the importance of research in determining 'what works' in correctional programming. They have begun to use information regarding 'evidence-based' practices to make decisions about the programs that they should implement. Thus, the likelihood that research may actually be the basis for criminal justice practice has never been greater. This attention to developing correctional programs based on sound principles and rigorous evaluation is long overdue. It has been more than 30 years since Martinson's famous article (Martinson, 1974) and 27 years since the National Academy of Sciences' (NAS) Panel on Research on Rehabilitative Techniques called for "research on criminal rehabilitation [with] rigorous [attention to] experimental design, theoretical rationale, and monitoring of integrity and strength of treatment" (Sechrest et al., 1979:10). Over a decade ago, the discussion focused on identifying the principles of effective correctional treatment programs that are critical to successful outcomes (Andrews, 1995; Andrews et al., 1990; see also Petersilia, 2004). More recently, the criminal justice field has been captivated by the call for "evidence-based programs" that federal policy makers are increasingly attentive to (Coalition for Evidence-Based Policy, 2006).