Maarten Hajer (1962, Groningen) is an internationally renowned Dutch political scientist and urban and regional planner. He was educated at the universities of Amsterdam and Oxford and published widely on issues of city politics, public space, political discourse, environment and democracy. Since 1998, he has been a professor of Public Policy at the University of Amsterdam.

In 2008, the Dutch Cabinet appointed him Director­–General of the PBL Netherlands Environmental Assessment Agency. While primarily focused on political decision–making in Holland PBL is also active for international bodies, such as the European Commission, OECD and UNEP.

After obtaining his DPhil from the University of Oxford, working with geographer David Harvey, he worked at the University of Leiden, at the Ludwig-Maximilians University of Munich, collaborating with sociologist Ulrich Beck, and as senior researcher at the Dutch Scientific Council for Government Policy (WRR), where he was project coordinator of a highly influential report on spatial development politics.

Hajer has held a number of public appointments. As a member of the VROM-council of the Dutch Ministry of Housing, Spatial Planning and the Environment he was responsible for the report on climate change as a structural spatial issue (“De Hype voorbij – klimaatverandering als structureel ruimtelijk vraagstuk” - 2007). In addition, he was a member of a party principles manifesto committee of the Dutch Labor Party (2000); a columnist for the Dutch newspapers Het Parool and Staatscourant; and a member of the jury for the Spinoza Prize, the Dutch EO Weijers competition for landscape architecture, and for EUROPAN 9, the European award for young architects; and board member of the Amsterdam Art Council and the Van Eesteren, Fluck van Lohuizen Stichting (EFL). Currently he is a board member of the Rotterdam Maaskant Prize for Architecture and a member of the UNEP Resource Panel (IRP) concerned with strategic issues of resource scarcity, decoupling and resource-efficiency.

Hajer is the author of many articles and books, among them Smart about Cities: Visualizing the Challenge for 21st Century Urbanism, with Ton Dassen (NAI010 Publishers / PBL, 2014); Strong Stories: How the Dutch Are Reinventing Spatial Planning, with Jantine Grijzen and Susan van ‘t Klooster, (010 Publishers, 2010); Authoritative Governance: Policy Making in the Age of Mediatization (Oxford UP, 2009); In Search of the New Public Domain, with Arnold Reijndorp (NAi Publishers, 2002); and the study The Politics of Environmental Discourse (Oxford UP, 1995).
He was the editor of Deliberative Policy Analysis – Understanding Governance in the Network Society, with Henk Wagenaar (Cambridge UP, 2003), and of Living with Nature, with Frank Fischer (Oxford UP, 1999).