Internationally, Leunbach was a respected name, being co-founder of the Verdensligaen for seksuel Reform (World League for Sexual Reform) in Copenhagen in 1927, while in Denmark he was met with massive resistance from most political parties, medical and ecclesial communities as well as the women's rights organisation Dansk Kvindesamfund.
Internationalt var Leunbach et respekteret navn, bl.a. som medstifter af Verdensligaen for Seksualreform i København i 1927, mens han i Danmark mødte massiv modstand fra de fleste politiske partier, lægelige og kirkelige kredse samt Dansk Kvindesamfund.