This article reviews some of the literature pertaining to futures markets. After briefly considering how the evolution of the institution of futures trading has required changing interpretations, we devote a longer section to the interplay between theory and evidence concerning intertemporal price relationships. While disputed and inconclusive interpretations persist, Working's theory of the price of storage and his revision of hedging doctrine are clear landmarks of progress in understanding these price relationships. We deal separately with hedging theory; then with the relation between futures and price variability; and finally with the stochastic attributes of futures prices.