Purpose/objectives: This descriptive, exploratory study of selected characteristics of RN (registered nurse) case management utilized secondary data from a randomized controlled trial in a 5-year Centers for Medicare & Medicaid Services (CMS)—funded Medicare Coordinated Care Demonstration (MCCD) project. Primary practice setting: The 1,551 older adult, community-dwelling Medicare beneficiaries in the study treatment group population had at least 1 of 5 qualifying chronic diseases (atrial fibrillation, congestive heart failure [CHF], coronary artery disease, chronic obstructive pulmonary disease, diabetes), a mean age of 75 years and an average of 4.5 comorbid conditions. Case management data documented by 14 RN case managers for 2002—2005 for all treatment group patients were analyzed, including a subgroup of 300 patients with CHF as a primary diagnosis. Design/methods: Nurse (registered nurse) case managers (NCMs) documented case management activities for all patients using 20 standard nursing intervention categories (NICs). Data reflecting the NCM time (in minutes) and mix of interventions were analyzed for patients in all 5 primary disease categories together. Using descriptive, parametric, and nonparametric statistics, the association of case management NIC, timing, and time provided to CHF patients’ inpatient admission risk was analyzed, as were patterns of NIC timing and timing for CHF patients. Findings/conclusions: All patients received an average of 60 min of case management time per month, slightly less than half of which was devoted to documentation of case management tasks by NCMs who had an RN-to-patient ratio of 1:135. Patients experiencing 2 or more inpatient admissions received slightly less case management time (p < .05) than patients with either 1 or no admissions during the study period. There was no specific rate (in minutes delivered per month) that was found to be associated with individual case managers and their CHF patients' associated readmission risk. Over time, NCM time allocated to routine monitoring exceeded that of self-care, disease, and medication education or counseling. Implications for case management practice: Further study of the impact of time, timing, and breadth of NCM intervention in chronic care case management outcomes is needed to better understand case management dosing effectiveness.