Wetland mitigation banking (WMB) is an organizational form that attempts to balance the ecological goals of wetland conservation and the economic goals of development with the aim of improving the implementation of wetland offsetting. Given the resulting tension, it is important to understand how the way stakeholders employ the WMB regulatory framework affects the goal of No Net Loss of wetlands. In this study, we interviewed WMB stakeholders in Florida in the United States to identify their strategies during negotiations around different aspects of defining wetland mitigation credits (e.g. service areas, types of credit and credit release schedules). Using the approach of New Institutional Economics, we found that within a framework of well-defined rules that nonetheless allow flexibility, WMB enables a field of action for negotiating within a zone of ecological-economic viability – in part due to the stakeholders’ interest in maintaining a good reputation in this field. Outside of this zone of viability a wetland mitigation bank proposal collapses for economic or ecological reasons.