The significance of this research rests on the premise that a greater understanding of professional and lay perspectives towards the mentally ill offender will help elucidate conflicting assumptions between agencies which, by their very nature, may be seriously disrupting the effective implementation of a number of key criminological and clinical policy initiatives involving the care and management of the mentally ill. In particular, consideration is given to the impact such ideological differences may have with regard to the establishment of community-based psychiatric care programmes, the policy of diverting mentally ill offenders away from the Criminal Justice System and into care by Health and Social Services, and the need to strengthen inter-agency co-operation.