The consultation-liaison (C-L) psychiatry services of seven university teaching hospitals in the United States, Canada, and Australia (the MICRO-CARES Consortium) used a common clinical database to examine 1039 consecutive referrals. A diagnosis of adjustment disorder (AD) was made in 125 patients (12.0%); as the sole diagnosis, in 81 (7.8%); and comorbidly with other Axis I and II diagnoses in 44 (4.2%). It had been considered as a rule-out diagnosis in a further 110 (10.6%). AD with depressed mood, anxious mood, or mixed emotions were the commonest subcategories used. AD was diagnosed comorbidly most frequently with personality disorder and organic mental disorder. Sixty-seven patients (6.4%) were assigned a V code diagnosis only. Patients with AD were referred significantly more often for problems of anxiety, coping, and depression; had less past psychiatric illness; and were rated as functioning better--all consistent with the construct of AD as a maladaptation to a psychosocial stressor. Interventions were similar to those for other Axis I and II diagnoses, in particular, the prescription of antidepressants. Patients with AD required a similar amount of clinical time and resident supervision. It is concluded that AD is an important and time-consuming diagnostic category in C-L psychiatry practice.