Patients with relapsed or refractory acute lymphoblastic leukemia (R/R ALL) have dismal outcomes, with survival of less than 6 months, and treatment options in the salvage setting have been limited to conventional cytotoxic chemotherapy with minimal activity. Advances in the development of novel targeted therapies have significantly improved outcomes in R/R ALL. Blinatumomab, inotuzumab ozogamicin, and chimeric antigen receptor (CAR) T-cell therapy constitute new treatment modalities that are challenging the historical regimens and paving a new path for treating patients with R/R ALL.