this paper should be cited as: Serano, J. (2009, June 12). Psychology, Sexualization and Trans-Invalidations. Keynote lecture presented at the 8th Annual Philadelphia Trans-Health Conference. Retrieved from http://www.juliaserano.com/av/Serano-TransInvalidations.pdf . author’s note: This paper was presented as a keynote lecture for the 8th Annual Philadelphia Trans Health Conference. I was inspired to write it after, on multiple occasions, I had read or heard sexologists and mental health professionals play down or outright dismiss trans people’s concerns regarding psychological depictions, diagnoses, terminology and theories about transgenderism.1 With this paper, I set out to explain, in very basic, easy to grasp language, precisely why trans people’s concerns regarding these matters are valid and should be taken seriously within the fields of psychology, psychiatry and sexology.