In the forty-four years since President Nixon signed the Endangered Species Act (ESA), states have become increasingly frustrated by the lack of meaningful opportunities for involvement in the Act’s implementation. This frustration has led to a national discussion on ESA reform, a Republican priority supported by the bipartisan Western Governors’ Association and others. The frustration stems from being relegated to a post-listing back seat, despite state primacy in the management of imperiled species prior to a listing as threatened or endangered under the ESA. This frustration is well placed, as this is not the role Congress intended states to play when it passed the ESA in 1973. Instead, under the long-forgotten section 6(g)(2) of the ESA, Congress provided states with the authority to oversee the implementation of the ESA post-listing. This Article advocates for the utilization of this never-implemented authority to achieve non-legislative ESA reform. In reaching that conclusion, this Article provides a uniquely comprehensive review of the legislative and regulatory history of the ESA, providing a clear demonstration of Congress’s intent to create a cooperative federalism regime under the ESA and the regulatory agencies’ refusal to carry that intent forward.