Stefaan Smis is researching how international crimes such as war crimes, crimes against humanity and genocide have been implemented in Congolese (Democratic Republic of Congo) national law and how Congolese judges use the concepts in their practice. The projects builds on an inter-university cooperation project with the Université Catholique de Bukavu (Eastern Congo) where a research centre (Centre Régional des Droits de l'Homme et de Droit International Humanitaire) has been created.

His publications include a co-authored book:

M. Cifende Kaciko and S. Smis, Code de droit international africain, 2nd ed., Bruxelles: Larcier, 2013, 608pp.