BACKGROUND: Evaluation of the referral, admission, treatment, and outcome of overseas patients admitted to a psychiatric hospital in central London. Ethical, legal and economic implications, and the involvement of consulates in the admission process, are discussed. METHOD: Assessment and review of overseas patients admitted between 1 January 1999 and 31 December 1999. Non-parametric statistical tests were used, and relevant outcomes described. RESULTS: 19% of admissions were overseas patients. Mean age was 38 years. 90% were unattached; 84% were white, 71% from European countries. 45% spoke fluent English. Differences in socio-economic status between home country and England were found. 74% were unwell on arrival; 65% travelled to England as tourists.65% of admissions came via the police. 32% had been ill for more than one year before admission; 68% had psychiatric history. 77% were admitted and 48% discharged under section of the Mental Health Act. 74% had psychotic disorders, all of them with positive symptoms. 55% showed little to moderate improvement in mental state; 10% were on Enhanced Care Programme Approach. Relatives of 48% of patients were contacted.The Hospital repatriated 52% of patients; the Mental Health Team followed up 13% of those discharged. The average length of admission was 43.4 days (range 1-365). Total cost of admissions was GBP350, 600 ($577, 490); average individual cost was GBP11, 116 (range GBP200-81, 000). CONCLUSIONS: Mentally ill overseas individuals are a vulnerable group that need recognition by health organisations to adapt current practice to better serve their needs. The involvement of consulates needs further evaluation.