Abstract: This study examined the influence of gender capacity-building practices on the performance of corporate social responsibility (CSR) programs at the Safaricom M-Pesa Foundation in Nairobi, Kenya. Anchored on Gender Role Theory and Feminist Theory, the study adopted a convergent parallel mixed-methods design, targeting 136 staff members. Qualitative insights were obtained from 35 respondents through key informant interviews, while quantitative data were collected via structured questionnaires from all 136 participants using a census sampling approach. Data were analyzed thematically for qualitative responses and statistically using SPSS for quantitative data. Findings revealed that gender-responsive practices significantly enhanced CSR performance, explaining 96.6% of the variance (R² = 0.966, p = 0.000). Among the predictors, gender-focused capacity-building had the strongest influence (β = 0.612, p = 0.000), demonstrating that equipping staff with gender-related skills and knowledge directly improves CSR outcomes. Other factors, including financial inclusion (β = 0.233, p = 0.011) and gender-focused technological innovations (β = 0.145, p = 0.000), also contributed positively, while gender representation in leadership showed no statistically significant effect. The study concluded that CSR effectiveness is maximized when gender capacity-building is inclusive, measurable, and aligned with community needs. It recommended the strategic integration of gender-focused training, systematic monitoring, and policy reinforcement to strengthen CSR program performance at the Foundation.