Substance abuse is one of the most frequent and serious problems encountered by human service workers, criminal justice professionals, and clinicians. Unfortunately, many professionals in these fields receive little, if any, formal training about this problem. Our planned encyclopedia presents state-of-the-art research and evidence-based applications in A-to-Z format. Rather than create a compendium of specific drugs and drug effects, for which there are any number of fine titles already available, the focus will be upon practical knowledge and skills for pre-service and in-service human service professionals, including substance abuse counselors and prevention specialists.