What can be learned from international experience of efforts to control spending and to improve efficiency and access in pharmaceutical markets? Policymakers tend to reinvent many policies to control the behavior of patients, doctors, and industry, despite a lack of evidence of those policies' cost-effectiveness. There is an emerging consensus that reimbursement in public and private health care systems should be informed by evidence of the cost-effectiveness of treatments and that utilization should be constrained by budget caps and information systems. Whatever the policy chosen, evaluation is as essential as it is rare.