This article covers much of the same territory as Bauer’s article from the same volume (Bauer 2009) except from a specifically Italian perspective. The concept of “sexual inversion” entered Italian medical literature in 1878, but female same-sex desire was a familiar concept already and was associated with excessive sexual longing, female masculinity, and certain women-only environments. The article looks at how those concepts were interpreted during the devopment of sexology as a study at the end of the 19th century.