Abstract: An improved system and method is provided for making trading markets using generalized trade reduction. To do so, a trade reduction engine may be provided to turn the implementation of an individually rational and incentive-compatible mechanism of a market maker engine for single-valued traders making trades in a particular trading domain into an implementation of a budget balanced, individually rational and incentive-compatible mechanism that may bound the loss in social welfare. In general, the generalized trade reduction methods find procurement sets of traders and remove them in iterations until conditions of competition among remaining traders may be fulfilled for trading to occur. Advantageously, the present invention may support many applications for making trading markets using generalized trade reduction for both procurement-class domains and class domains.