Under brand new rules implementing the Physician Payments Sunshine Act (Sunshine Act), a wide range of financial relationships, including many research-related payments, between industry, physicians, and teaching hospitals will be publicly disclosed through comprehensive, standardized payment reporting. The Sunshine Act represents the latest in a series of regulatory attempts to address financial conflicts of interest that may bias research conduct and threaten subject safety. This article summarizes the major aspects of the Sunshine Act affecting medical research, how it interacts with existing laws and policies, and identifies important unresolved issues and implementation challenges that still lie ahead with the rollout of the legislation underway. The Sunshine Act primarily depends on disclosure as a regulatory tool. As such, its long-term impact remains open to question. Disclosure in this context may have limited utility given, among other reasons, uncertainty about who the intended recipients are and their ability to use the information effectively. Apart from the insufficiency of transparency, this article further explores how proportionality, fairness, and accountability considerations make optimal regulation of financial conflicts in medical research quite challenging.