Century 21-opoly is a marketing/promotional board game released by Century 21 Real Estate. It is a derivative of Monopoly and its game play is identical to Monopoly in most respects. The primary difference is that the properties, utilities, cards, etc. are oriented to the Century 21 Real Estate corporation. Aside from this, using the roll-and-move mechanic, players buy properties, build houses and hotels, and collect rent from fellow players. The player who doesn't go bankrupt is the winner.