During a six-month period, 306 psychiatric assessments were recorded prospectively on specifically designed schedules. There was a skewed distribution towards younger patients, and 78% were male. Just over half were seen for a court report, one-third of cases came from solicitors, and in two-thirds the request was merely for advice. Secure care was only sought in 15%. In nearly two-thirds an offence had precipitated the referral. Half were seen in prison. The majority had a history of dangerous behaviour and one-fifth were regarded as a sexual risk to others. Only one-third had not previously seen a psychiatrist. A personality disorder was diagnosed in 41%, but only 6% were considered to be psychopaths. These and other findings are discussed to help give an insight into the service.