Rolef de Weijs conducts research on national and international rules of insolvency law, meaning the rules that apply when individuals or companies are no longer able to pay their debts. He investigates distribution issues surrounding the bankruptcy of businesses in a complex society, in which he combines research in the field of law and economics. De Weijs focuses on how insolvency law affects the financing of companies, and thus also the behavior of companies and their directors and shareholders.

De Weijs lectures in the courses on Insolvency Law, European Insolvency Law, and Critical Analyses of Corporate Finance and Insolvency Law. He has been a visiting professor at the Riga Graduate School of Law in Latvia since 2012 and is a board member of the Master's programme in Law, Markets and Behavior and the specialised Master’s in Corporate Law at the Zuidas, both of which are offered jointly by the UvA and Vrije Universiteit Amsterdam. In his teaching, De Weijs challenges his students to take a critical view at current law. He trains students to identify patterns of opportunistic behavior and evaluate the extent to which the law succeeds in setting limits to such behavior.

De Weijs has worked at the UvA since 2005, first as a doctoral researcher and since 2013 as an associate professor. He studied law and philosophy in Groningen (1993-1999), completed a Master's degree in Japanese language and culture (Japan Prize Winners Programme, 1999), and obtained an LLM from Harvard Law School (2001). In 2005 he obtained his doctorate with a thesis entitled Faillissementspauliana, Insolvenzanfechtung & Transaction Avoidance in Insolvencies. Since 2001 he has worked at the law firm Houthoff Buruma, as an attorney and later also as a court appointed trustee. He is the chief editor of European and International Insolvency Law Studies and Boom Updates Insolventierecht, and an editor of Kluwer Recht & Praktijk, Insolventierecht and Groene Serie Faillissementswet.