Over the last decades, trifluoromethyl copper(I) complexes have played a key role as reactive species in C–CF₃ bond-forming reactions. This Short Review not only covers selected examples of relevant copper-mediated or catalyzed nucleophilic trifluoromethylation reactions, which is one of the most active fields in organic synthesis, but also provides a comprehensive picture of the real behavior of these copper species, including ubiquitous cuprates, in the reaction media.