When agencies of the federal government procure supplies, federal laws and regulations require that they use a competitive process. The Federal Acquisition Regulations (FAR) detail two procedures to accomplish this—sealed bidding and competitive negotiation.
Sealed bidding is usually inappropriate for the procurement of complex services and manufactured goods. It is used for procurements based on price and when discussion of the bids is unnecessary. Agencies tend to use sealed bidding for routine construction, repairs, off-the-shelf supplies, and relatively non-complex services (e.g., custodial services).