Paying for performance in primary medical care: learning about and learning from "success" and "failure" in England and California.

Paying physicians to hit performance targets is becoming increasingly fashionable, as evidenced by the growing number of "pay-for-performance" programs in the United States and beyond. This article compares pay-for-performance initiatives in two nations--the United Kingdom and the United States. It pays particular attention to the context in which the initiatives were conceived and implemented, factors which are largely neglected in the pay-for-performance literature. Despite some glowing reviews of the UK national pay-for-performance program for primary care doctors, we suggest that such programs face significant technical obstacles in all cases and particularly severe institutional obstacles in the United States.