While there are a growing number of interventions and evaluations of programmes aimed at changing gender norms and violence against women and girls, there remains a dearth of documentation outlining the challenges faced in conducting these interventions and evaluations, particularly in traditional and low literacy settings. The Do Kadam Barabari Ki Ore (Two Steps Towards Equality) programme sought to understand what works to prevent violence against women and girls in Bihar, India. This paper draws insights from process evaluation data. It describes promising features and challenges of implementation, and characteristics which weaken the potential effects of complex, community based, social sector programmes that aim to change deeply entrenched gender power hierarchies. We drew on the Medical Research Council framework for process evaluation in analysing our process evaluation data, and focus on mechanisms of impact, and factors inhibiting programme success, including contextual and implementation challenges. The paper also outlines measures that may help overcome observed challenges and areas that require modifications and/or further investigation. The programme experienced several challenges. These included contextual issues, such as the lack of leadership skills of those delivering the intervention and the gap between expected responsibilities and activities of government platforms and reality. Implementation challenges were encountered in reaching men and boys, younger women and the community at large and ensuring their regular attendance; and in maintaining the fidelity of the intervention activities. Our insights call for an evidence-supported dialogue on these challenges and how best to anticipate and address them.