Some differences in the organization of liaison psychiatry between the United States and the United Kingdom are discussed. The fact that much psychiatric morbidity in general hospital patients is unrecognized justifies an expansion of liaison services particularly where referral rates are currently low, as they are in British hospitals. However, it is important that there should be an evaluation of these services together with an assessment of the complementary role of the liaison nurse. It is also suggested that liaison psychiatrists could make a greater contribution to medical student teaching than they do presently.