Geert van Calster's practice focuses on international litigation (conflict of laws/ private international law), EU and international environmental law, international trade law (law of the World Trade Organisation) and European economic law, subjects on which he also publishes and speaks extensively.

He advises clients on topics such as jurisdictional issues in international litigation, choice of law/ applicable law in international transactions, recognition and enforcement of court orders outside of jurisdiction, European waste law, nanotechnology regulation and Environmental Impact Assessment.

He has also been involved in a number of anti-dumping, state aid and internal market cases, as well as issues of international trade law (WTO: GATT, TBT, SPS, SCM).

Prof. Dr. Van Calster represents clients before the European Commission and in national and the European courts.