The articles presented in this issue offer an array of policy-relevant studies in an area that has become increasingly important to both the public and third-party payers. Although it is believed that appropriate utilization of drugs can contribute to containing the growth of health care costs, the impact of appropriate prescribing, dispensing, and use of drugs associated with costs of hospitalizations and physician visits is generally unavailable. As new, ever-more-expensive drugs come to market, comprehensive studies of utilization, expenditures, prices, quality, and cost effectiveness will enhance the policy process.