The advent of T-cell-mediated immunotherapy has led to a new era in the treatment of relapsed, refractory B-cell lymphomas and leukemias. Chimeric antigen receptor T-cell and engineered T-cell receptor therapies have demonstrated impressive efficacy in treating refractory disease. The principal toxicities of these therapies include cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome (ICANS), but others exist as well. Cytokine release syndrome and ICANS are typically acute events occurring within 30 days of therapy, but other on-target/off-tissue toxicities may persist for years. There is no currently accepted single approach to managing all aspects of cytokine release syndrome and ICANS. However, there are clear trends in many areas and a clear need for further consensus surrounding others. This article will discuss T-cell-mediated immunotherapy complications and their suggested management. It is not intended to be comprehensive or applicable to every patient, so practitioners should exercise sound clinical judgment. Rather, this may serve as a starting point for further management discussions in the community.