Background Chimeric antigen receptor (CAR)-modi ed T cell therapy has shown great potential in the immunotherapy of patients with hematologic malignancies. In spite of this striking achievement, there are still major challenges to overcome in CAR T cell therapy of solid tumors, including treatmentrelated toxicity and speci city. Also, other obstacles may be encountered in tackling solid tumors, such as their immunosuppressive microenvironment, the heterogeneous expression of cell surface markers, and the cumbersome arrival of T cells at the tumor site. Although several strategies have been developed to overcome these challenges, aditional research aimed at enhancing its e cacy with minimum side effects, the design of precise yet simpli ed work ows and the possibility to scale-up production with reduced costs and related risks is still warranted. Conclusions Here, we review main strategies to establish a balance between the toxicity and activity of CAR T cells in order to enhance their speci city and surpass immunosuppression. In recent years, many clinical studies have been conducted that eventually led to approved products. To date, the FDA has approved two anti-CD19 CAR T cell products for non-Hodgkin lymphoma therapy, i.e., axicbtagene ciloleucel and tisagenlecleucel. With all the advances that have been made in the eld of CAR T cell therapy for hematologic malignancies therapy, ongoing studies are focused on optimizing its e cacy and speci city, as well as reducing the side effects. Also, the efforts are poised to broaden CAR T cell therapeutics for other cancers, especially solid tumors.