Over the past decade, the federal regulation of methane from oil and gas activities on public land has borrowed heavily from state regulation. During this time, Colorado has played a prominent role in regulatory efforts to reduce methane emissions from oil and gas operations. Much of the focus has come from the state’s Air Quality Control Commission (AQCC) and, to a lesser extent, the Colorado Oil and Gas Conservation Commission. Colorado’s efforts have influenced important federal regulation, including the U.S. Environmental Protection Agency’s (EPA) New Source Performance Standards, 40 C.F.R. Part 60, Subpart OOOOa (Quad Oa) rulemakings and the U.S. Department of the Interior, Bureau of Land Management’s “Waste Prevention Production Subject to Royalties” (Venting and Flaring) rulemakings.