British Society for the Study of Sex Psychology

The British Society for the Study of Sex Psychology (BSSSP) was founded in 1913, "to advance a particularly radical agenda in the field of sex reform, based on the writings of gurus such as [Edward] Carpenter and [Havelock] Ellis." In 1931 the Society was renamed the British Sexological Society.
It seems to have continued until some point in the 1940s.
The society was particularly concerned with homosexuality, aiming to combat legal discrimination against homosexuality with scientific understanding. Members included George Cecil Ives, Edward Carpenter, Montague Summers, Stella Browne, Laurence Housman, Havelock Ellis, Bernard Shaw, and Ernest Jones.
The Society published a series of pamphlets: