The objective of this study was to estimate some economic values of Mud Lake, a managed, lacustrine wetland on the Minnesota-South Dakota border. Several outputs of Mud Lake were identified and an economic value was estimated for each. Flood control was valued at approximately $440 per acre, based on dollar damages prevented; water supply, using public utility revenues, was valued at $94 per acre; fish/wildlife habitat, recreation, and aesthetics were valued at about $21 per acre using the Contingent Valuation Method; and corrective expenditures were used to evaluate water quality at a negative per acre value of $180. When capitalized at 6 percent, the estimated total annual value of these four outputs is $6,250 per acre. These values can assist managers and policy makers in making decisions regarding the opportunity costs of Mud Lake management options or of wetland alterations or preservation. These snapshot values of Mud Lake "at the margin" are estimated under the assumption that all other wetlands and water resources in the region are unchanged.