This study tests whether managerial experience improves firm productivity using panel data from the World Bank Enterprise Surveys (2006–2013) for Tanzania. Labour productivity is measured as log sales per worker, and managerial experience as log years of experience. Using fixed-effects and first-difference models, the results show a robust negative relationship (elasticity ≈ −0.5), indicating that increased managerial experience is associated with lower productivity. This contradicts standard theory and suggests that, in constrained environments, experience may reflect managerial rigidity rather than productivity-enhancing learning