This chapter reviews empirical and theoretical work within critical studies on men and masculinities (CSMM), drawing on extensive empirical and theoretical studies relevant to psychology and social psychology. The chapter focuses on gender relations and power dynamics, social structures, intersectionality, bodies, practices, and identities, both individual and collective. The chapter first maps the key theoretical developments of CSMM, historically and conceptually, before moving to focus on two important contemporary issues: first, the development of more egalitarian masculinities, and, second, the explanations for various non-egalitarian masculinities, such those linked to incel and Alt-Right movements, both online and offline.