After graduating in economics (specialisations: microeconomics, antitrust policy) Niels Philipsen started a Ph.D. research in the field of Law and Economics at the Maastricht Institute for Transnational Legal Research (METRO). He obtained his Ph.D. degree in December 2003 on the topic "Regulation of and by pharmacists in the Netherlands and Belgium: An economic approach".

In 2003 Niels Philipsen worked at the European Commission (DG Competition) in Brussels. In Summer 2005 he was a visiting scholar at the University of Illinois in Urbana-Champaign (USA), and in Spring 2007 he was a “European Visiting Professor” at Peking University in Beijing (China).

From 2004 to 2006 he was a postdoctoral researcher in the NWO-programme "Shifts in Governance". Since 2007 he has been working as a Senior Researcher in various research projects (including contract research for, inter alia, various ministries, European Commission, OECD, insurers, and professional organizations). He teaches on Law and Economics, international competition law and EU State aid policy.

In 2013 he became Vice-Director of METRO, the Maastricht European Institute for Transnational Legal Research, located at the Faculty of Law.

On 1 July 2016, Niels Philipsen was appointed Professor of 'Shifts in Private and Public Regulation' (0.2FTE) at the Erasmus School of Law in Rotterdam.

On 16 November 2016, he was equally appointed Adjunct Professor of the School of Law and Economics at the China University of Political Science and Law in Beijing.