Immunosuppression is a primary concern after orthotopic liver transplantation (OLT). On the one hand, the graft is at jeopardy through acute or chronic rejection, and on the other, immunosuppression and antirejection therapy increase the risk of infectious complications. Effective immunosuppression therefore should prevent rejections without leading to a high rate of infections, bearing in mind the fact that infections and infection-related complications are the most frequent causes of early death after liver transplantation. With more specific immunosuppression the infectious complications can potentially be minimized. Antithymocyte globulin (ATG) and the first monoclonal antibody OKT3 immunosuppression are non-specific. The replacement of these antibodies in a quadruple immunosuppressive regimen with the new monoclonal IL-2R antibody BT 563 probably reduces the early infection rate. We report on our first experience with BT 563. The incidence of infection was compared with a historical control group with ATG.