This article examines the contract design decisions of three federal agencies—the Departments of Health and Human Services, Defense, and Homeland Security—using five years of data from the Federal Procurement Data System. Three basic contract design elements are charted—type (fixed price versus cost reimbursement), length, and value—across simple to complex products. All three agencies use short-term, fixed-price contracts for the majority of the purchases that they make. This basic contract design allows agencies to tap the benefits of competition: innovation and cost-efficiency. However, the Departments of Defense and Homeland Security often dramatically increase the length and value of contracts through modifications to initial agreements. This approach forgoes the benefits of competition and may expose the agency to the risk of cost overruns, delivery delays, and diminished product quality.