Buy American Act in Brief: Preferences for 'Domestic' Supplies and Construction Materials in Federal Procurements [February 26, 2014] [open pdf - 301KB]
"The Buy American Act of 1933 is the earliest and arguably the best known of various statutes regarding federal procurement of domestic products. Essentially, the act attempts to protect U.S. businesses and labor by restricting the acquisition and use of end products or construction materials that are not 'domestic.' For purposes of the act, domestic end products and domestic construction materials include (1) unmanufactured end products or construction materials mined or produced in the United States, as well as (2) end products or construction materials manufactured in the United States, provided that (a) the cost of the components mined, produced, or manufactured in the United States exceeds 50% of the cost of all components, or (b) the product is a commercially available off-the-shelf item. End products or construction materials that do not qualify as domestic under these definitions are generally treated as foreign, and offers that supply foreign end products or construction materials are foreign offers, regardless of the offeror's nationality. Purchases of services are generally not subject to the Buy American Act."
CRS Report for Congress, R43140