The European Union (EU) is currently facing unprecedented challenges to its problem‐solving capacity, such as those represented by pressing transnational crises and by bottom‐up criticisms towards the European integration process. Moreover, the EU is said to compensate its weak input legitimacy with an enhanced problem‐solving capacity. However, the notion of problem‐solving itself has remained remarkably vague in the multilevel governance (MLG) literature. This symposium analyses problem‐solving in different MLG settings. In this introduction, we identify procedural and operational notions of problem‐solving in MLG, and present a structural framework to guide the comparative analyses of multilevel systems along the dimensions of political integration, functional differentiation and decentralization. The contributions to the symposium illustrate how structural elements of different multilevel systems shape both the policy‐making process and the politics of problem‐solving within these systems. In doing so, they pave the way for further comparative research.