The management of "wicked" policy problems is among the most provoking challenges of today's public services. Being highly resistant to resolution, they challenge the capacities of traditional governance structures and public budgets. For the first time, Rittel and Weber defined "wicked" problems in 1973. They argue, that the fact that social realities are increasingly understood as complex and interconnected networks made up of a variety of open systems make it more difficult to figure out where social problems are ultimately rooted. This paper tries to disentangle those complexities, based on the following question: "What are the conditions for integration and performance management (PM) to become effective mechanisms able to manage wicked policy challenges in the public sector?" The major idea is based on a "policy trilemma" between wicked issues, integration and PM: while both are understood as tools to manage wicked issues, integration requires organisational boundaries to dissolve, while the same boundaries are exactly what PM is based on. The paper is a collection of theoretical insights that define success factors for disentangling the trilemma. Using the case of child poverty in the UK and the Republic of Ireland existing policies and practitioner's views are put into relation to those theoretical factors to see whether there might be non-conformities.