Consensus does not yet exist about the definition of case management as it is practiced in the care of long-term mentally ill patients. Case management interventions may be arrayed on a continuum, with brokering and clinical approaches at the poles. However, most actual case management programs fall along the continuum and not at the extreme poles. The functions of case management in the care of long-term patients correspond closely to nine principles of continuity of care that transcend specific case management styles. The nine principles are an administrative climate supportive of long-term patients, ready access by patients to the services they need, provision of a full array of services, individually tailored treatments, flexible program offerings, linkage among agencies serving the patient, a continuing relationship between patient and caregiver, patient involvement in service planning, and recognition of cultural factors affecting treatment. The author discusses how the concept of continuity of care can be used in considering policy issues such as staffing of case management services and suggests that service systems may find it advantageous to offer several different case management approaches to accommodate patients' individual needs.