The growing complexity of regional planning and design, in combination with increasing concerns about climate change and resource depletion, has revived the discussion on strategic thinking. Spatial planning and landscape architecture develop long-term visions to facilitate the gradual adaptation of the physical environment. Despite accomplishments in both disciplines, the two domains have yet to exploit the full potential of a joint approach to long-term regional design. The objective of the multidisciplinary study reported in this paper was to explore alternative means of developing imaginative yet robust long-term visions. The study combined literature study with the development of several long-term visions for the creation of sustainable energy landscapes. This paper focuses on the emerging methodological framework for long-term regional design, and argues that three modes of change should be integrated into the design process: change due to current projected trends, change due to critical uncertainties and intended change. Subsequently, a five-step approach to the development of long-term visions is derived and illustrated in this paper. The second paper of this two-part series, which will be published in the April 2012 issue of European Planning Studies, centres on the application and the discussion of the five-step approach to integrated visions.