Congestive Heart Failure is a costly debilitating medical condition that affects millions of elderly people. This Clinical Practice Improvement study was under taken to determine how variation in patient characteristics and clinical processes impact patient outcomes including length of stay, total charges, and increased severity of illness during hospitalization. The AHCPR Guideline for Heart Failure was used to evaluate clinical care. Data on patient characteristics including severity of illness and process of care were analyzed to determine which variables had the greatest impact on outcomes of care. Results showed that patient characteristics including comorbidities, severity of illness, and noncompliance with diet were significantly related to longer lengths of stay, higher charges, and/or increased severity (all covariates, p < .05). In addition, process of care variables including medication use and patient education significantly (p < .05) impacted outcomes of care. Findings have implications for the development of practice guidelines designed to improve patient outcomes associated with CHF hospitalizations.