His research has focused on agent-based simulation of social interaction, social interaction in and around computer game play, social ontology and agent models, use of social media in online education, and issues of design for hybrid social spaces. He has published over 100 peer-reviewed papers, book chapters etc. and guest edited special issues of journals such as Computational and Mathematical Organization Theory, Journal of Gaming and Virtual Worlds, and Logic Journal of the IGPL. His publication list is available via http://harko.blogs.dsv.su.se/.