On matters of business rescue and insolvency he served as consultant to IMF (Indonesia), World Bank (Georgia), the U.S. Federal Reserve System (Fed) and the Dutch Ministry of Justice. He is an advisor of the European Commission regarding a new legal framework of crisis management for cross-border banking groups, in the preparation of the legislative texts for the revision of the EU Insolvency Regulation and the drafting of the March 2014 Recommendation on a New Approach to Business Failure and Insolvency. He advised with legal opinions or acted as an expert witness in European or international insolvency related questions in Dutch courts as well as in the courts of New York, London, Warsaw, Alexandria (Va., USA), Vienna, Dublin, Rhodes (Greece), Zürich, Los Angeles and Stockholm.

He published (in Dutch) hundreds of articles in leading legal journals and some twenty-five books. He is the single author of: Wessels Insolventierecht (Wessels Insolvency Law), a 10 Volume series, 3rd edition, published between 2010 – 2012, by Kluwer, The Netherlands. Since 2013, in the 4th edition, four volumes have been published.

Together with professor Miguel Virgós (University Autónóma, Madrid), he was author of the European Communication & Cooperation Guidelines for Cross-border Insolvency (‘CoCo Guidelines’, 2007). Together with professor Ian Fletcher (University College London) he was reporter on the American Law Institute – International Insolvency Institute’s Global Principles for Cooperation in International Insolvency Cases (2012). Other publications in the English language include EU Banking and Insurance Insolvency. An Annotated Guide and comments on the implementation of EC Directives 17/2001 and 24/2001 in EU Member States, Oxford University Press, 2006, 620 pp. (Gabriel Moss and Bob Wessels (eds.)); International Cooperation in Bankruptcy and Insolvency Matters, Oxford University Press, New York, 2009, 268 pp. (with Hon. Judge Bruce A. Markell and prof. Jason J. Kilborn), International Insolvency Law, Deventer: Kluwer, 3rd ed., 2012, 1232 pp, and Harmonisation of Insolvency Law in Europe, Deventer: Kluwer, 2012 (with prof. Ian Fletcher).

Prof. Wessels was Commerzbank Visiting professor Institute for Law and Finance, Johann Wolfgang Goethe University, Frankfurt (2003). Other visiting professorships include University of Pretoria (2004), St. John’s University, New York (2006 – 2011); Riga Graduate School of Law, Riga (2008 – 2012);  University of Istanbul (2012); CEU Universidad San Pablo, Madrid (2012).

He furthermore is: Deputy Justice at the Court of Appeal in The Hague; Member of the Joint Board of Appeal of the three European Supervisory Authorities (ESAs; ESMA, EBA and EIOPA respectively); Chair of the International working group to assist the American Bankruptcy Institute (ABI) in its programme to renew U.S. Bankruptcy Code’s Chapter 11; past Chairman of the Netherlands Association for Comparative and International Insolvency Law; past Chairman of the Academic Forum of INSOL Europe; former member of the Committee to renew the Dutch Bankruptcy Act; Emeritus Director of International Insolvency Institute; Fellow of the American College of Bankruptcy; Member of the American Law Institute; Member of the European Law Institute, Honorary Member of INSOL Europe and Honorary Member of Netherlands Association for Comparative and International Insolvency Law.