||This dissertation presents studies on the use of medetomidine, ketamine, and atipamezole for sedating and immobilizing mammals in captivity. The species studies were markhor (Capra falconeri megaceros), snow leopard (Panthera uncia), and blue fox (Alopex lagopus). The objectives of the study were to investigate the effects of the drugs, to compare the efficacy of the drugs, and to establish useful dose levels. Tables, charts, and graphs complement the text. Six papers on which the thesis is based are appended.