The United States government (plaintiff) initiated a condemnation proceeding to acquire 50 acres of land owned by the city of Duncanville, Texas (the city) (defendant). The site had been used as a sanitary landfill. In order to replace the condemned landfill, the city acquired another site and developed it into a larger and better facility. The city argued that it was entitled to recover the costs incurred in acquiring the substitute facility. But the United States government contended that just compensation should be determined by the fair market value of the condemned facility. The district court heard expert testimony concerning the sale prices of sanitary-landfill facilities and entered judgment for the fair market value of the condemned facility. The court of appeals reversed, and the United States government appealed to the United States Supreme Court.