[en] The price and duration of natural gas contracts are analysed to determine that electric and gas utilities in the USA can obtain long-run reliable supplies of natural gas at prevailing market prices. Open access to gas transmission lines has created a market with a large number of buyers and sellers that provides reliable gas supplies. The transaction cost literature on contracts suggests that spot purchases and short-term contracts have become more efficient than the long-term fixed price contracts that typified the gas industry before the 1980s. An efficient supply of gas requires increasing contracting options and reducing regulatory approval of contracts. Some regulatory inefficiencies are avoided by automatically setting the allowable cost of gas to current market prices. (author)