Given the diversity in FLT3 inhibitor potency, resistance patterns, and toxicity profiles, ideally the oncologist will have a range of FLT3-directed therapies to choose from, similar to TKI selection in chronic myelogenous leukemia, so that a particular FLT3 inhibitor could be matched to an individual patient’s needs. The gene discussed is FLT3; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.