Antonio Siccardi is Professor of Biology and Genetics at the University of Milan. He got his M.D. at the University of Pavia in 1968. He worked in London, Stanford, Paris, Bethesda, Seattle, Bethesda again and Munich. His encounter with IgE was in 1975, in Africa, while studying Pygmy population genetics with Luca Cavalli-Sforza. Back in Pavia, he worked on the genetics of atopy for a few years. His more relevant contribution to medicine (with Giovanni Paganelli) has been the development, in the ‘90s, of tumor targeting strategies for diagnostic and therapeutic purposes in patients. IgE has been the last (and still very promising) effector system he has tried to target on mice tumors.