This thesis examines the land use planning process where development applications involve wetlands along the Ontario coastlines of the Great Lakes. The goals are to understand how local planning implements wetland policy within the hierarchy of environmental governance, and why it produces a given outcome at the local level. The objectives are to identify decision making factors, to determine how they influence outcomes, and to depict the research findings in a conceptual framework. Eight case studies were completed, based on a review of planning documents and interviews with professional planners and politicians. Each study examines the decision making process, the negotiated natural heritage issues, and the roles of the actors. Nineteen key findings are made that relate to the status of wetland policy implementation, the types of natural heritage issues that local planners encounter, the roles of the actors during the planning process, and the potential impacts of environmental governance on the principles of democracy.