With competing explanations circulating through popular culture and the academy about what masculinity is, this chapter explores the various theories and concepts being made available by academics and researchers in the field. Through a brief historical overview of the different approaches that have underpinned masculinity studies, the chapter establishes the various models that have been employed to capture the nature of men’s lives. It introduces the reader to the different philosophical, theoretical and methodological approaches to the study of masculinity. More specifically, the chapter engages with the notion of ‘cultural epistemology’, the evidential framework that is used to explain men’s attitudes and behaviours. One of the themes to emerge from this discussion is to recognise how masculine subjectivities are subject to the structural reproduction of gendered inequality, oppression and sexual violence. At the same time, the chapter also highlights how masculinities are also contextually driven. However, rather than simply repeat existing commentary in the field, the chapter opens up the discussion to explore how masculinity is constituted, drawing upon Queer Theory and Trans Studies.