The National Science Foundation funds construction of large science and engineering infrastructure projects, like telescopes, that can take years to build and cost hundreds of millions of dollars. Since our March 2019 report, 4 major NSF construction projects had no increases in their authorized costs or schedules. For example, the Daniel K. Inouye Solar Telescope is on track to be completed within its $344.1 million budget by June 2020. NSF implemented 2 of our 6 prior recommendations, including revising policies for its major-project cost estimates. NSF has begun to address the remaining recommendations on its project management practices.