This Programmatic Environmental Assessment (EA) has been prepared by the National Aeronautics and Space Administration (NASA). This Programmatic EA will assist in the decision-making process as required by the National Environmental Policy Act (NEPA) of 1969, as amended (42 United States Code U.S.C.] 4321 et seq.), Council on Environmental Quality (CEQ) Regulations for implementing the provisions of NEPA (40 Code of Federal Regulations CFR] Parts 1500 through 1508), NASA's policies and procedures at 14 CFR Subpart 1216.3, and Executive Order (EO) 12114, Environmental Effects Abroad of Major federal Actions. This Programmatic EA provides information associated with the potential environmental impacts of the transition and retirement (T&R) of NASA's Space Shuttle Program (SSP). The T&R of the SSP would consist of the disposition of both real property (land, buildings and other structures and their associated built-in systems that cannot readily be moved without changing the essential character of the real property) and personal property (all assets not classified as real property owned by, leased to, or acquired by the government). Property disposition activities are the primary focus of this EA because this is the T&R activity with the greatest potential for environmental impacts. The Programmatic EA approach allows NASA to assess the overall T&R activities, although some specific options are not yet sufficiently developed to assess in detail.