In this interview Jeroen Slot (head of Research & Statistics, Municipality of Amsterdam) and Kees van Paridon (former chief science officer, municipality of Rotterdam) share their ideas and reflect on their extensive experience with linking scientific knowledge and local policy making. They discuss the divergence between established institutions and emergent knowledge needs and the problematic entwinement of scientific knowledge and policy development. Conditions are proposed for the design of intermediaries between the academic and governmental sectors.

Given the scientific and social importance attached to productive interactions between science and policy practices, there is a striking lack of insight into current knowledge practices and the dilemmas they lead to. Our special issue can’t solve this deficiency but it can provide an impetus for opening up current knowledge practices, reflect on the role of science in them and instigate a more systematic exchange of methods. A warning is given for the reification of boundary work and Gabrielle Bammers’ Implementation and Integration Sciences is introduced as framework for the analyses.

When scientific values like objectivity, validity and reliability are inadequate for designing research that enables society’s capacity for dealing with unstructured problems, which values or criteria should we use for designing adequate knowledge practices? Based on the articles in this special issue we answer this question by analysing the methods researchers have used for selecting stakeholders, knowledges, synthesis, context and outcome in new knowledge practices. Although a common language for comparison and documentation is lacking, the analysis provides recommendations for better designing interaction between scientific and other practices. The most important message however is that we need a designated platform for exchanging and evaluating experiences and discussing methods and the outcomes they yield.

In his much praised book on mayors, Benjamin Barber argues it’s up to cities to address the world’s most acute problems. These include wicked problems such as climate change, terrorism, poverty and trafficking of drugs, weapons and humans. Cities are not only excellent problem solvers, they are also given a prominent role in innovation and economics, democracy and citizenship, and more recently domestic care. Complicated, wicked and thus knowledge intensive problems are stacking up at the local level. But where to get the appropriate knowledge to tackle these issues?