Background and aims: Intimate partner violence (IPV) prevention ultimately hinges on change at the level of the household where relationships are conducted. There is little research examining the process of relational change among couples with a history of IPV following exposure to a community level IPV prevention intervention, particularly in low-income settings. This thesis aims to fill this gap by examining how relational change occurred (or did not) among couples in Uganda exposed to SASA!, a community mobilization intervention aimed to prevent IPV and HIV. The study first explores relationship change processes among couples exposed to the intervention. Secondly, it examines the key aspects of the intervention and social network factors that influenced these changes, illuminating the pathways through which the intervention diffused. Methods: This thesis comprises: i) a methodological examination of qualitative dyadic (couple) data collection and analysis; ii) a qualitative study of couples exposed to the SASA! intervention using in-depth interviews to examine processes of relationship change; iii) a mixed methods analysis of the influence of intervention and social network factors in the diffusion of new ideas and behaviour around intimate relationships and IPV. Findings & Conclusions: Through examining relationship trajectories from both partner’s perspectives the sphere in which IPV occurs comes through clearly, revealing the common challenges couples faced, how they were shaped by gender roles and, also, how they were able to change, preventing IPV. Change is possible through key community-level interventions working with both men and women that generate hope and belief in an alternative way of achieving fulfilling relationships and family life. This includes providing simple tools to improve relationships and local change agents to support change, all within the context of a wider community that is changing together, generating new norms in the process. Thus, the IPV prevention field may benefit from the inclusion of relationship education/skills and support for both men and women at the community level.