World League for Sexual Reform

[2] Representatives came from many countries: England, the United States, Canada, Germany, France, Russia, Austria, Switzerland, Czechoslovakia, Italy, the Netherlands, Belgium, Spain, Japan, Norway, Sweden, Denmark, Iceland, Lithuania, Egypt, Liberia, Argentina, Chile, the British Indies, and Malaysia.

Congress speakers included: Hirschfeld, Norman Haire, Vera Brittain, Dora Russell,[7] Charles Vickery Drysdale (from the Malthusian League), Stella Browne, Ernst Gräfenberg, Marie Stopes, M. D. Eder (a pioneer psychiatrist), Laurence Housman, George Ives, Eden Paul, Alexandra Kollontai, Max Hodann, Felix Abraham [de] (who with Dr Ludwig Levy-Lenz performed the world's first sex-change operation in 1931 at Hirschfeld's Institut für Sexualwissenschaft in Berlin), Bernard Shaw, Bertrand Russell, Ethel Mannin,[7] Harry Benjamin, Peter Schmidt, William J. Robinson (an American contraception crusader) and Jack Flügel, a Freudian psychologist who assisted Norman Haire and Dora Russell organize the Congress and also led the Men's Dress Reform Party.

[9] Magnus Hirschfeld, the British physician Havelock Ellis and Swiss psychiatrist Auguste Forel were elected the first presidents of the World League.

From 1930, Norman Haire and Dane Jonathan Leunbach replaced the elderly and largely inactive Ellis and Forel, but they remained Honorary Presidents.

Whilst based in Berlin, Turville-Petre was an active member of the Scientific-Humanitarian Committee, which campaigned for gay legal reform and tolerance, and attended the Second Congress in Copenhagen in 1928.