OBJECTIVES: Since 2006 physicians have been able to select the competitive drug acquisition program (CAP) as an alternative method of acquiring drugs and biologics for in-office administration under Medicare. This study examines the evolution of the program from 2006 to present, recounts the legislative and regulatory program impacts and describes issues that remain as potential obstacles to widespread provider acceptance. METHODS: Historic CAP regulatory and legislative guidance was collected, arranged in order of issuance, abstracted and analyzed. A timeline illustrating evolutionary program modifications was constructed. Remaining issues that may deter provider participation were described and information resources were compiled. RESULTS: The CAP is a payment model that removes the drug purchasing function from the physician’s office while the drug administration responsibility remains. Despite intent to minimize provider financial risk and ease operational burden, the CAP has been slow to attract participants. There have been legislative and regulatory attempts to modify and improve the program’s attractiveness and ease of use however the majority of physicians providing in-office drugs continue to do so through conventional buy and bill methods. Throughout this time the Medicare drug payment to physician offices has remained at average sales price plus six percent (ASP +6%) and the associated drug administration rates have been fairly stable. CONCLUSIONS: The number of providers utilizing the buy and bill method was expected to decrease following implementation of the CAP alternative. The CAP program has now been in effect for over two years, has undergone a number of operational modifications, and yet continues to experience low enrollment. At this time it is not possible to determine conclusively the impact of: 1) inadequate provider incentive to drive the conversion, or 2) the deterrent effect of remaining program issues. Further investigation is warranted.