The International HIV/AIDS Alliance has produced this case study collection in order to help projects to conduct work identifying strategies that will be effective in reaching out to different groups of men and enabling them to change their attitudes and behavior regarding HIV/AIDS. It presents experiences and lessons from a range of different projects (some supported by the Alliance and some not) that are working with men. By showcasing experiences and lessons from the field in the form of case studies, this collection offers inspiration, ideas and models for working with different kinds of men in a range of contexts. These case studies not only describe HIV/AIDS projects that are working with men, but also other kinds of projects that address other issues and problems relating to men (for example, gender identity, sexuality, violence).