The emergence of humanistic philosophy in the field of psychology has greatly influenced conceptualizations of gender and gender development. Humanism is constituted by a set of theoretical suppositions that emphasize human potential, personal agency, and the irreducible nature of human experiencing. From this perspective, gender identity development is a dynamic and fluid process, shaped by sociocultural constructions of gender, relational interactions, and individual meaning-making systems. This entry illustrates the pivotal figures in humanism and the humanistic movement in psychology, major therapeutic concepts, and how these ideas influence mental health professionals’ understanding of gender. Also discussed are current trends in humanistic philosophy in light of recent social justice efforts and the effects of this shift on theories of gender development. The entry concludes with a discussion ...