Donath-Landsteiner hemolytic anemia accounts for one third of all immunologic hemolytic syndromes in pediatric patients. Diagnosis is suggested by results of the direct Coombs test which is positive with anti-C3d, evidence of erythrophagocytosis on admission blood smears, and results of the Donath-Landsteiner test. Anti-P specificity should be routinely looked for. Management, required once the diagnosis is established, is symptomatic. Warmed red blood cell concentrates should be used for blood transfusions. Exposure to cold should be avoided. Use of maintenance corticosteroid therapy is no longer acceptable.