The past decade has witnessed significant advances in the assessment of the risk of violent behavior toward others. Some of the most noteworthy advances include increased research on shorter-term outcomes, a multisite study funded by the MacArthur Foundation and the National Institute of Mental Health using an expanded range of predictor variables and more carefully defined and sensitive outcome measures of violence and aggression, and the development of tools to help clinicians focus on relevant risk factors for violence. Others are the increased use of meta-analysis to assess risk factors for crime and violence, the focus on developing actuarially based tools validated to measure level of risk for future violence and offending, and increased attention to interventions that reduce risk.

The authors of Violent Offenders: Appraising and Managing Risk have actively contributed to these advances in risk assessment. Indeed, this book describes a research program that began 25 years ago, centered at the maximum-security division of the Mental Health Centre in Penetanguishene, Ontario. After discussing the historical and methodological contexts of the research, the authors describe their work in violence risk appraisal with three populations: mentally disordered offenders, fire setters, and sexual offenders. They appropriately assume that risk factors for one of these populations may be different, or arrayed differently, than for others.

The authors next describe the development of the Violence Risk Appraisal Guide (VRAG), a tool designed for the relatively long-term prediction of who will be violent. They offer data and summarize arguments relevant to the VRAG's use, but anyone familiar with the violence risk literature over the past decade will be aware that the VRAG is clearly the tool of choice when the purpose is predicting violent behavior over a relatively long period (a mean outcome period of 88 months for the derivation sample) with mentally disordered offenders.

Violent Offenders also documents another major contribution to risk prediction and reduction. In a chapter on reducing the risk of future violence, the authors present the results of an empirical approach to establishing a treatment program for hospitalized mentally disordered offenders. The approach is more sophisticated than the usual current one of selecting dynamic risk factors (those potentially changeable through planned intervention) from among the predictors in the literature and building a risk-reduction program around them. Instead, the authors' empirical study of risk-relevant treatment needs for the population under investigation yielded the following target areas for intervention: management problems, aggression, anger, substance abuse, life skills deficits, active psychotic symptoms, social withdrawal, and family problems.

Despite the greater methodological sophistication of this approach, the list of target areas is reassuringly similar to what could be derived from a review of the current broader literature on violence. This consistency should serve to remind hospital and agency staff working with mentally disordered offenders that it is currently reasonable to design a treatment program that has a primary goal of reducing future crime and violence. It should also underscore the importance of research questions on risk reduction that must be addressed as the field moves toward implementing such approaches. Issues such as efficacy versus effectiveness in research designs, treatment integrity, sensitivity of outcome measures of crime and violence, and the enrollment of sufficient numbers of participants across sites must be considered if we are to learn what works, with whom, at what level of effectiveness, and in what context in the reduction of violence risk.

Violent Offenders: Appraising and Managing Risk is an important book. Its strengths include the description of a research program on violence with different populations and the derivation of a tool, the VRAG, that is both relatively accurate for long-term predictions of violence for mentally disordered offenders and efficient to use. The book also cogently summarizes the arguments in favor of actuarial prediction, addressing many of the concerns raised by clinicians who have been reluctant to consider such methods, and it describes an empirical approach to measuring risk-relevant treatment needs and designing a program to address them.

The application of this material has limits, which the authors tend to carefully acknowledge. The VRAG would not be applicable as a tool for predicting violence and crime by individuals not involved in the criminal justice system. It places individuals in one of nine overall risk levels, which is useful for considering overall level of risk but relatively insensitive to identifying specific risk-relevant intervention areas or change in risk status; a VRAG level is determined almost entirely by historical and clinical factors that do not change.

Thus clinicians seeking to develop risk-reduction programs or individual risk-reduction treatment plans must use the VRAG in combination with other approaches that address these questions. How a clinician, or a decision maker, can accurately determine when risk has been reduced is not a question that the VRAG can answer—but it remains a crucial area for investigation, perhaps employing strategies such as those described by the authors in their chapter on risk reduction.

Violent Offenders: Appraising and Managing Risk is highly recommended for clinicians, researchers, clinical administrators, judges, attorneys, and all others who must address questions related to the risk of future violent behavior among various populations. It offers a model approach to operationalizing and measuring risk of violence, and it outlines important considerations for the field as it weighs how such material will be applied.

Dr. Heilbrun is professor and chair of the department of clinical and health psychology at MCP-Hahnemann University in Philadelphia and is codirector of the law and psychology program at MCP-Hahnemann and Villanova School of Law.