Spatial planning in the Netherlands is shifting from regulatory toward more developmental modes of planning. This paper explores the background of these changes and discusses current approaches to developmental planning, especially in rural areas. It combines views reXected in planning theory with the accumulated experiences of a project in the southern part of the Netherlands, called Heuvelland. The Heuvelland project is aimed at the mobilisation of market parties for spatial developments. It is an attempt to circumvent the path-dependency in which many current spatial innovation projects get caught up, owing to established institutional planning and policy arrangements. We argue that in order to stimulate innovation and create a new economic base for rural spatial developments, new economic actors and new public-private structures and networks must be mobilised. We consider how this can be done, taking into account the importance of sustainable regional development.