There is a major problem of civilian-perpetrated gender-based violence (GBV) in conflict zones and, in response to this, men are increasingly becoming involved in GBV prevention programmes. There is limited evidence on the implementation of these programmes in settings affected by armed conflict. The aim of this study was to explore the approachesused and the challenges faced when implementing GBV sensitisation programmes with civilian men in conflict-affected settings. Grounded theory qualitative research methodology was used. Semi-structured interviews were conducted with 18 purposively selected expert key informants with knowledge and experience of implementing male GBV sensitisationprogrammes with conflict-affected populations in a number of different countries. The respondents highlighted the importance of understanding the cultural and socio-political context, engaging with local religious and community leaders, using male community members as programme staff and peer leaders, and appealing to more constructive ideals of masculinity. Challenges included the risk of potentially reinforcing gender stereotypes, marginalising women’s empowerment programmes, and a number of political, cultural and economic barriers. A weak evidence base and limited technical capacity also impeded programme implementation. The study highlights the need for a stronger evidence base and more detailed guidance to help to improve the effectiveness of male sensitisation programmes in settings affected by armed conflict.