For over half a century in the United States, there have been two competing theories of what a merger remedy is, fundamentally. Some courts and federal antitrust agencies have viewed merger remedies as a unique form of regulated commercial behavior, categorically distinct from precipitating transactions and worthy of a remedy specific antitrust analysis and standard (the “Enforcement Theory”). Some courts and merging parties, on the other hand, have viewed proposed remedies as part and parcel to their precipitating transactions and properly subject to the same well-established inquiry into competitive effects (the “Transactional Theory”). The article details the history and ongoing contest between the Enforcement and Transactional Theories, analyzing their strengths and weaknesses and proposing solutions for resolving the conflict.