The article discusses the assessment and management of toxicities associated with chimeric antigen receptor (CAR) T-cell therapy, a promising treatment for various cancers. CAR-T-cell therapy can induce rapid and durable clinical responses but is associated with unique acute toxicities, including cytokine-release syndrome (CRS) and CAR-T-cell-related encephalopathy syndrome (CRES). CRS can range from low-grade constitutional symptoms to severe multiorgan dysfunction, and rarely, it can evolve into fulminant haemophagocytic lymphohistiocytosis (HLH). CRES is the second most common adverse event, often occurring concurrently with or after CRS. The authors emphasize the importance of intensive monitoring and prompt management of these toxicities to minimize morbidity and mortality. They describe the multidisciplinary approach adopted at their institutions and provide recommendations for monitoring, grading, and managing acute toxicities in patients treated with CAR-T-cell therapy. The article also includes a clinical case study and detailed guidelines for grading and managing CRS, CRES, and HLH/MAS.The article discusses the assessment and management of toxicities associated with chimeric antigen receptor (CAR) T-cell therapy, a promising treatment for various cancers. CAR-T-cell therapy can induce rapid and durable clinical responses but is associated with unique acute toxicities, including cytokine-release syndrome (CRS) and CAR-T-cell-related encephalopathy syndrome (CRES). CRS can range from low-grade constitutional symptoms to severe multiorgan dysfunction, and rarely, it can evolve into fulminant haemophagocytic lymphohistiocytosis (HLH). CRES is the second most common adverse event, often occurring concurrently with or after CRS. The authors emphasize the importance of intensive monitoring and prompt management of these toxicities to minimize morbidity and mortality. They describe the multidisciplinary approach adopted at their institutions and provide recommendations for monitoring, grading, and managing acute toxicities in patients treated with CAR-T-cell therapy. The article also includes a clinical case study and detailed guidelines for grading and managing CRS, CRES, and HLH/MAS.