While some practice preferences have emerged in relapsed B-ALL (CD19 CAR for post-HSCT relapse or HSCT ineligible, inotuzumab for high disease burden or proliferative disease, and blinatumomab for MRD + disease with an available transplant donor), patient and logistical preferences must be taken into account when selecting therapy. The gene discussed is CD19; the disease is acute lymphoblastic leukemia.