The demand of a new generation of public services is leading to a systematic exploration of what design can do for public organizations. The article presents and discusses, through the analysis of two design projects conducted in the Municipality of Turin, a designbased theoretical framework for organizational change based on the conduction of long-term processes of engagement and exposition of public sector employees to the design culture. The two cases show that the growth of innovation capacity in the public sector based on service design practices must consider the necessity of coping with long-standing challenges, i.e. the innovation of/in public bodies; the peculiarities of organizational learning processes and of the absorpti...