In this chapter, we analyze and discuss outcomes of a collaborative landscape planning process carried out over a long period and involving different types of farmland owners and other stakeholders, including public authorities. The case study concerns a small watershed drained by the Odderbæk stream in Denmark. We see the case as a comprehensive study of what can be considered a successful collaborative landscape planning process. Different types of landowners, organized in a collaborative stream association (OSA), and in collaboration with public authorities and other actors worked together to manage landscape-related problems. At an early stage, the OSA developed a strategy that subsequently became highly influential for the overall collaboration between the farmland owners and for guiding a large number of landscape changes within the watershed. These include re-meandering the stream, establishing new walking trails, converting arable land to extensive grazing pastures, re-grazing of abandoned pastures, preserving historic features, and establishing and restoring ponds for amphibians. We conclude that a well-functioning board of OSA, capable of raising funds for activities, making connections with different knowledge and power institutions including the local government, and not least creating thrust among its members, has been essential for the governance processes.