Speaking from the 1st European CAR T-Cell Meeting, held in Paris, France, Alexey Bersenev, MD, PhD, of Yale University, New Haven, CT, outlines how manufacturing of CAR T-cells can be improved to minimize ‘out of specification’ CAR T-cell products. This meeting was co-organized by the European Society for Blood & Marrow Transplantation (EBMT) and the European Hematology Association (EHA).