Base Closure and Realignment (BRAC): Background and Issues for Congress [April 25, 2019] [open pdf - 1MB]
From the Summary: "Since 1977, statutory thresholds have effectively constrained the President's ability to close or realign major military installations in the United States. Congress has instead periodically granted temporary authorities--known as a Base Realignment and Closure (BRAC)--that have established independent commissions for the review and approval of basing changes submitted by the Secretary of Defense. These unique and transient authorities last expired on April 16, 2006. There have been five rounds of base closures: 1988, 1991, 1993, 1995, and 2005. [...] This report provides background on the development of BRAC, describes its major elements and milestones, and outlines issues frequently cited in the context of new rounds, such as potential savings."
CRS Report for Congress, R45705
Congressional Research Service: https://crsreports.congress.gov/