This field experiment examines output quantity and quality for workers in a data input business. We observe two sets of workers that differ in monitoring intensity as they move from time to piece rates. The application of piece rates increases quantity, and we find that the resultant quality can be improved with sufficient monitoring. "Committed" workers also produce higher quantity and quality, showing the role of worker selection - which appears especially strong under time rates. Our results thus show how a firm can refine its worker selection and monitoring options together with the payment system to deliver its chosen quality-quantity combination.