R. Karl Hanson, Ph.D., C.Psych., is one of the leading researchers in the field of risk assessment and treatment for individuals with a history of sexual offending. Originally trained as a clinical psychologist, he was a researcher and research manager in the area of corrections and crime policy for Public Safety Canada between 1991 and 2017. Dr. Hanson has published more than 175 articles, including several highly influential reviews. He is the lead author of the Static-99R, STABLE-2007, and ACUTE-2007 risk tools, which are widely used for assessing the risk and needs of individuals with a history of sexual offending. Based in Ottawa, Canada, he is currently President of the not-for-profit organization SAARNA (Society for the Advancement of Actuarial Risk Need Assessment) and adjunct faculty in the psychology department of Carleton University (Ottawa). His most recent book is Prediction Statistics for Psychological Assessment (2022).