In patients with chronic heart failure, fluid retention (or hypervolemia) is often the stimulus for acute decompensated heart failure that requires hospitalization. The pathophysiology of fluid retention is complex and involves both hemodynamic and clinical congestion. Signs and symptoms of both hemodynamic and clinical congestion should be assessed serially during hospitalization. Core heart failure drug and cardiac device therapies should be provided, and ultrafiltration may be warranted. Critical care, intermediate care, and telemetry nurses have roles in both assessment and management of patients hospitalized with acute decompensated heart failure and fluid retention. Nurse administrators and managers have heightened their attention to fluid retention because the Medicare performance measure known as the risk-standardized 30-day all-cause readmission rate after heart failure hospitalization can be attenuated by fluid management strategies initiated by nurses during a patient’s hospitalization.