The Trading Agent Competition (TAC) combines a fairly realistic model of the Internet commerce of the future, including shopbots and pricebots, with a challenging problem in automated reasoning and decision making. Automated trading via auctions under severe time constraints are to be con-ducted by entering autonomous agents into TAC, assuming the role of travel agents. The TAC game rules, as well as a description of the discrete op-timization problem faced by an agent that wishes to allocate goods to its clients, are described. The TAC’01 entry “006”, encapsulating a constraint programming solution, is explained in some detail.