Spatial planning has been earmarked as an important tool for achieving sustainable development. In Sweden the important task of planning for sustainable spatial development and land use falls largely to the local authorities, since there is no official institute for spatial planning at a national or regional level. This article investigates local planning for sustainable development by analysing recent municipal comprehensive plans, which it is argued are a major instrument for this purpose. Although comprehensive plans are statutory, their design and content is very much at local discretion, and for the most part, not a rigid process governed from above. For this reason, a template analysis was used, where the template was built from the contents of the comprehensive plans, and not from a predefined understanding of what sustainability is or how planning for sustainable development should be done. What the findings reveal, however, is that there is not much deliberation concerning the meaning(s) of sustainable development, and, further, that the planning principles considered necessary to bring about sustainable development were not exclusively regarded as sustainable as such, but rather as part of a general 'belief system' about prudent planning-sustainable or not. It is suggested that, rather than rethinking planning, planners have internalized the concept of sustainable planning into the existing 'belief system,' and thus, the planning principles have become 'sustainable' by default.