Summary: Pursuant to a congressional request, GAO reviewed the impacts of closing Meigs Field Airport, focusing on: (1) its role in the Chicago-area and national airport system; (2) the effect of redistributing Meigs Field's traffic to other area airports; and (3) the City of Chicago's obligations to the Federal Aviation Administration (FAA) under the Airport Improvement Program (AIP). GAO found that: (1) although Meigs Field has been designated as a primary commercial service airport within the National Airport System, commercial service at Meigs Field has been limited due to numerous operational constraints; (2) studies conducted by the City of Chicago estimate that the redirection of Meigs Field traffic to area airports will not significantly impair service, increase noise or compromise safety; (3) the City of Chicago is not obligated to keep Meigs Field open because of a special condition in its AIP grant agreement that states the City must reimburse FAA for some of the improvements funded by the grants if it does not renew its lease; and (4) FAA did not follow its standard procedure to ensure that the City of Chicago had a long-term lease for Meigs Field before rewarding AIP grants.