The management of nonpoint source water pollution presents an immense challenge to economists and policy makers alike. A complex array of physical, economic, political and institutional barriers lie between theoretically appealing textbook prescriptions and their transition into successful real-world solutions. Underlying beliefs about property rights, interest group politics and the transaction costs associated with designing and implementing successful measures have all played a particularly critical role. Building on the theoretical literature and the lessons provided by the practical use of economic instruments for nonpoint source water pollution management around the world, this paper considers these issues in the context of the Swan-Canning river system in Perth. Four innovative economic instruments for the management of nonpoint source nutrient pollution in that system are discussed: auctioned best management practice payments; best management practice incentive charges; an urban nonpoint source emissions offset bank; and a catchment based licensing/trading program.