Subjective aspects of social support and loneliness were examined in a group of 30 forensic inpatients in secure units and were compared to a control group of 31 surgical inpatients. The secure-unit patients were more lonely and experienced the deficiencies in their social relationships in a different way to the controls. Loneliness for the secure-unit patients was a more unpleasant experience and more associated with difficulties in forming close attachments. There was a high correlation between loneliness and the personality trait of psychoticism in the secure-unit group which was not found in the controls. These results underline the serious problems of these patients with relationships and suggest the development of intervention programmes.