The causes of hemolytic anemia are numerous and a systematic approach is critical for proper identification and classification. The direct antiglobulin test can establish the diagnosis and subclassify the majority of autoimmune hemolytic anemias. Further testing to identify the driver of AIHA can have significant implications in overall management. Advanced testing for rare nonimmune acquired hemolytic anemias or hereditary hemolytic anemias may be necessary if DAT testing is negative.