Today’s emerging Co-design processes between citizens and civil servants in helixes groups, produces multiple challenges for the interaction designer. How can these challenges produce new merging roles and communication strategies for interaction designers for use in Co-design processes? This thesis focuses on the design research process outcomes from Co-design processes between civil servants and citizens in urban development processes. The tangible outcomes will be elicited through the merging of practice-based know-how as seen through the eyes of an interaction designer with a bifocal lens on Social psychology and Behavior economics. This research process produces tangible outcomes in the form of educational material, communication methods and strategies for interaction designers, civil servants in Co-design processes. Additional outcomes are digital communication strategies for city operations based on the need for increased citizen involvement in the urban development process.