Successful cartelization requires two characteristics: demand should be relatively inelastic, and the cartel must be able to control most of the supply. OPEC succeeded in the short run because the short- run demand and supply of oil were both inelastic. CIPEC has not been successful because both demand and non-CIPEC supply were highly responsive to price. A cartel faces two organizational problems: agreement on a price and a division of the market among cartel members, and it must monitor and enforce the agreement.