he passage of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA)

and the ensuing rollout of the outpatient drug benefit in January 2006 have focused attention on ensuring elderly patient access and cost-effective prescribing and use of drugs. Those responsible for Part D program administration within the Centers for Medicare and Medicaid Services (CMS) and pre-scription drug program sponsors share the formidable task of managing both the cost and quality of drug regimens for more than 40 million Medicare beneficiaries. Medicare will become the largest single payer of drug benefits in the United States, with a projected $70 billion in expenditures in 2006.1 The elderly have more chronic illnesses and use more prescription drugs than any other age segment, increasing the like-lihood of adverse drug events, many of which are avoidable.2-4 In an attempt to ameliorate the cost burden and ensure rationale and optimal drug use, Congress took the novel approach o