The study examines 102 young people with Learning Disabilities (n = 51) and without a learning disability (NLD; n = 51) to explore ways in which LD young people with harmful sexual behaviours (HSB) should be recognized as a subgroup requiring specialized treatment and intervention. Throughout this comparison of perpetrator, victim and abuse characteristics the similarities between the two groups are confirmed repeatedly. NLD young people had experienced domestic violence more often at home and had a history of property offences, lending support to suggestions of their more generalized criminality. Contrary to expectation, there were no significant differences in terms of victim choice. LD young people did engage in "nuisance" behaviours, e.g. exposure, but they also engaged in a wide range of offence behaviours, e.g trickery. NLD young people, however, exhibited an even wider range of offence behaviours, e.g. vaginal penetration. Investigative and treatment implications are discussed. (Contains 3 tables.)