An integer programming formulation for the minimum cost design of precast, prestressed concrete simply supported beams is developed. The cross section and gridwork within which strands must be placed are assumed given, and the design problem is to determine the concrete strength and the number, location, and draping of strands that minimizes the total cost of the beam. Constraints limit release and service load stresses, ultimate moment capacity, cracking moment capacity, and release camber. A box girder for a multibeam highway bridge is designed to demonstrate the computer program written to implement the methodology. ASCE.