Acute myelogenous leukemia (AML) describes a group of related hematologic malignancies that are being approached therapeutically from several perspectives. Conventional chemotherapeutic agents, such as anthracyclines and cytosine arabinoside (Ara-C), are useful in treating AML but now appear to have reached their maximum potential. Newer therapeutic approaches to AML have recently focused on immune-based therapy through monoclonal antibodies that target and destroy malignant cells via specific cell receptors. One such agent is gemtuzumab (CMA-676), an agent that targets the CD33 antigen on malignant myeloid cells. Initial studies have shown significant anticancer activity. We will discuss traditional and newer therapeutic approaches to AML and review the role of monoclonal antibody based therapies for patients with AML. A case of a 30-year-old man with refractory AML who was treated with gemtuzumab will be mentioned, highlighting potential applications and possible limitations to this novel therapy. Despite the effective reduction in the number of malignant cells in bone marrow, gemtuzumab ineffectively treated extramedullary leukemic gingival infiltrate. Regardless of limitations, monoclonal-based therapy offers an exciting and potentially safer adjunctive therapy for patients with AML.