This chapter discusses the influence of ideological bias in the psychological study of sex and gender, with a focus on academic psychology. After introducing the essence of the problem, the chapter examines the conceptual distinction between "sex" and "gender", the binary nature of biological sex, and the challenges to the idea of a sex binary. The following sections provide a survey of recent introductory textbooks and generalist journals, as well as a historical overview of sex and gender in psychology from the late 19th century to the present day. The chapter ends with a consideration of the current state of the field, its future prospects, and suggestions to limit the growing influence of ideological bias in relation to sex and gender.
