 The discovery of estrifluoromethyl diaryl sulfonium salts by Yagupolsky and his colleagues was a major breakthrough in the field of trifluoromethylation. This led to the development of several electrophilic trifluoromethylating reagents, including those from the groups of Omomoto, Shreve, Adachi, Magner, Tani and Shibata. These reagents are now commercially available and widely used in the pharmaceutical, agricultural and material industries. This article was authored by Noriyoshi Bata, Andrei Matsnev and Dominique Kahard.