Shrinkage or ‘no growth’ is expected to condition the long-term perspective of many Western cities and regions. Planning for shrinkage differs substantively from planning for growth and therefore calls for a change of thought in spatial planning. In our paper, we analyse how planning professionals responded to a ‘planning for shrinkage’ challenge in a regional design competition. We found that they fully adapted to the shrinking perspective, took a strategic approach, and promoted a leading role for local inhabitants. Collaboration with local inhabitants and entrepreneurs, creating new alliances, and timing emerge as key themes for planning professionals in planning for shrinkage.