This paper presents findings from a field experiment conducted during the period 2015-2018 measuring the impact of Better Factories Cambodia on worker pay, work hours, work concerns, life satisfaction and productivity. The programme is found to lead to a decrease in working hours among workers while increasing take-home pay. Productivity rises, though not as fast as wages. The analysis contributes to the literature on establishing a positive impact of social compliance on productivity and worker wellbeing, and measuring the distribution of gains between workers and firms.