Six "pure" types of case-manager activity are identified using chart data from 922 cases in the Medicare Alzheimer's Disease Demonstration. The association between case-manager actions and client characteristics, and between case-manager activities and service use outcomes is used to test predictive validity. Case-manager activity is generally more associated with caregiver than client characteristics. Monitoring and service management was protective against nursing home placement. A clinical nursing emphasis was protective against hospitalization. Understanding how case management is differentiated may improve staffing, treatment protocol, and client service outcomes.