In addition to standard first-price and second-price auctions, this program implments multi-round ascending-price (English) or descending-price (Dutch) auctions, when prizes have common-value and/or private-value components. In the English auction, the bid price is raised sequentially until only one interested bidder remains. The English auction has a number of options, e.g., with clock-driven price increases, or with hidden proxy bids as in an eBay auction. Alternatively, it is possible to allow public bids that raise the provisional price as in the FTC bandwidth spectrum auctions. In contrast, prices are reduced in a Dutch auction until one bidder accepts the current price and stops the auction. The Anglo-Dutch auction is a hybrid that begins with ascending bids, but switches to a Dutch auction when only two active bidders remaining.