The thesis investigates how new forms of public leadership can contribute to solving complex problems in today’s welfare societies through innovation. A bottom-up type of leadership for collaborative innovation addressing wicked problems is theorised, displaying a social constructive process approach to leadership; a theoretical model emphasises that leadership emerges through social processes of recognition. Leadership is recognised by utilising the uncertainty of a wicked problem and innovation to influence collaborators’ sensemaking processes. The empirical setting is the City of Copenhagen in which a strategy- and policy-making process is launched by a handful of professionals and a middle-manager with an in-depth knowledge of area-based planning programs in disadvantaged neighbourhoods. The objective is increased coordination across municipal administrations and social housing organizations. A crucial condition for success is iterative leadership adaptation. In conclusion, the thesis finds that specialized professionals are indeed able to develop politically viable, innovative and collaborative solutions to wicked problems; and that such professionals are able to transform themselves into an actual, yet temporary, leadership, fully able to navigate the uncertainties and conflicts that characterise large political organisations.