The Kibera Slum in Nairobi, Kenya is a densely populated area where female community health volunteers (FCHVs) play a vital role in addressing gender-based violence (GBV). FCHVs provide essential services to their communities and often encounter GBV-related issues. Previous studies have explored the effectiveness of GBV prevention programmes but lack long-term impact assessments. The research employs qualitative methods including in-depth interviews with FCHVs and focus group discussions. Data collection was conducted from January to March , encompassing all FCHVs currently serving in the Kibera area. Over the five-year period, there was a significant reduction (47%) in reported GBV incidents among the FCHVs who participated in GBV prevention programmes. The findings suggest that while initial participation in GBV prevention programmes had an immediate positive impact, sustained engagement and support are crucial for maintaining these reductions over time. Policy makers should prioritise long-term sustainability of GBV prevention initiatives by integrating them into existing community health programmes and ensuring ongoing training and resources for FCHVs.