This book provides an insight into the nature of masculinity and the possibility of change in men's lives, using case studies and tracing the history of ideas about masculinity and analysing new research data. Masculinities offers a comprehensive introduction to, and a remarkable synthesis of, a new field of knowledge and politics. It examines and assesses the history of attempts to create knowledge of the nature of masculinity by psychoanalysts, social scientists, and movements for social change. Connell argues that, while the goal of a science of masculinity is mistaken, we can gain fresh ways of thinking about men's bodies and men's involvement in a gendered world. There is not "one" masculinity, but multiple masculinities, which can be understood through a social analysis of gender relations. Contemporary developments in masculinities are examined through a close focus on the lives of four groups of men, interviewed especially for this study, who are undergoing different experiences of change - some working to transform gender relations and some resisting change. Their trajectories towards and away from hegemonic masculinity are traced in detail; some of these accounts are highly amusing while some are tragic. After this detailed analysis of the lives of particular men, Masculinities moves to a larger arena, and shows that modern masculinities are products of a 400-year history in which gender was closely connected with empire and the creation of a global economy. New forms of politics about masculinity have recently emerged. The final sections of the book examine these new forms as they have occurred in Western countries, including the currently fashionable "masculinity therapy", and discuss how men can pursue social justice in a gendered world.