John Callender (MB Chb, MD, MRCPsych, FRCPsych) is a Scottish psychiatrist and philosopher born in 1954. Callender graduated from the University of Glasgow in 1977. He is a consultant psychiatrist at the Royal Cornhill Hospital in Aberdeen, the associate director of Grampian Medical Health Services and an Honorary Senior Lecturer at the University of Aberdeen. He was one of the four entry-points for transgender healthcare in Scotland, serving the Grampian, Orkney and Shetland areas, but has now retired. He lives in Aberdeen with his wife and three children.