We have identified several general temporal-abstraction mechanisms needed for reasoning about time-stamped data, such as are needed in management of patients being treated on clinical protocols: simple temporal abstraction (a mechanism for abstracting several parameter values into one class), temporal inference (a mechanism for inferring sound logical conclusions over a single interval or two meeting intervals), and temporal interpolation (a mechanism for bridging non-meeting temporal intervals). Making explicit the knowledge required for temporal abstractions supports the acquisition of planning knowledge, the identification of clinical problems, and the formulation of clinical-management-plan revisions.