TAC was designed to create a benchmark problem in the complex domain of e-marketplaces and to motivate researchers to apply unique approaches to a common task. Their goals included providing a benchmark problem in the complex and rapidly advancing domain of e-marketplaces (Eisenberg, 2000) and motivating researchers to apply unique approaches to a common task. Another key feature of TAC was that participating agents competed against each other in a preliminary round and many practice games leading up to the nals. Thus, developers changed strategies in response to each others' agents in a sort of escalating arms race. Leading into the competition day, a wide variety of scenarios were possible. A successful agent needed to be able to perform well in any of these possible circumstances.