Adolescent sexual abusers are a highly heterogeneous group and, compared with adult abusers, there is a paucity of research to guide risk prediction, decision making and evaluation. This chapter is divided into four sections. The first considers what is known about sexual and general recidivism in adolescents. It argues, on the basis of currently available research, that with adolescents the risk of both violent and general reoffending appears greater than the risk of sexual recidivism. Well-designed and standardised assessment measures are the central building blocks of effective evaluation. Because of this, section two provides a brief guide to some of the main considerations relevant to psychological test design particularly as they apply to the assessment of adolescent abusers. The third section provides a brief introduction to the Adolescent Sexual Abuser Project (ASAP), a multisite UK study designed to improve the understanding of dynamic risk factors in adolescent abusers. The final section provides information on the ASAP findings specifically with regard to general and victim empathy, and cognitive distortions.