Liaison psychiatry has been recognised in many countries as a special interest or sub-speciality of psychiatry concerned with the management of general hospital patients with psychological problems. However, despite increasing awareness of the emotional and behavioural aspects of illness, it has yet to achieve substantial influence within psychiatry and, more importantly, has had only modest effects on the delivery of medical care by physicians and other specialists. Recognition of its potential by planners and commissioners has been disappointing. Regrettably, in the UK and elsewhere, recent changes in the organisation of health care could hinder its development. This paper argues that in order to make substantial progress there is a compelling need to solve a fundamental obstacle – the separation between psychiatric and general medical care. This requires:

(a) convincing the psychiatric profession that consultation-liaison is a distinct sub-speciality;

(b) continuing efforts by liaison psychiatrists to define their special expertise and to demonstrate that their services are effective and acceptable to medical colleagues and to patients;

(c) persuading those who organise health care that liaison psychiatry services need to be provided and administered as an integral component of comprehensive medical care.