The US Endangered Species Act is the most comprehensive law any nation has enacted to protect imperiled species. Many of its protections come from section 7 of the Act, but how government regulators use this tool is poorly understood. Our analysis is the first to systematically evaluate how the US Fish and Wildlife Service has implemented section 7 over an extended timeframe and across all listed species. We analyze data on all 88,290 consultations recorded by FWS from January 2008 through April 2015. In contrast to conventional wisdom about section 7 implementation, no project was stopped or extensively altered as a result of FWS finding jeopardy or adverse modification during this period.We also show that median consultation duration is far lower than the maximum allowed by the Act, and several factors drive variation in consultation duration. The results discredit many of the claims about the onerous nature of section 7 but also raise questions as to how federal agencies could apply this tool more effectively to conserve species. We build on the results to identify ways to improve the effectiveness of consultations for imperiled species conservation and increase the efficiency of consultations.