Firms are increasingly looking to eradicate social and environmental non-compliances at their suppliers in response to increasing regulations, consumer demand, potential for supply chain disruptions, and to improve their social, environmental, and economic supply chain performance. This study develops a model of the relationship between the buyer’s supplier incentives and penalties for the supplier’s social and environmental compliance, and the outcomes in terms of reduction in supplier social and environmental violations as well as the buyer’s own operating costs. This model is tested empirically through analysis of a dataset of opinion-based survey responses from practitioners at 334 companies across 17 industries. The analysis finds specific penalties and incentives that are positively associated with reduced supplier violations and reduced buyer operating costs. In particular, offering suppliers incentives of increased business and training for improving social and environmental performance is strongly associated with a reduction in both violations and operating costs.