2017: Program chair (together with Petra Hendriks and Hans van Ditmarsch) of the Lorentz workshop The Invention of Lying: Language, Logic and Cognition in Leiden.

2015: Program co-chair (together with Wander Jager and Andreas Flache) of the 11th Social Simulation Conference ESSA 2015 in Groningen.

2014: Second Workshop Reasoning About Other Minds in Groningen; together with Jakub Szymanik.
The Proceedings of the Second Workshop Reasoning About Other Minds are online.

2012: Logic and Cognition, at ESSLLI in Opole; with Jakub Szymanik.
The proceedings of Logic and Cognition are online.

2012: Special session The Turing Test and Thinking Machines at the conference Computability in Europe, in Cambridge; together with Mark Bishop.

2012: Modeling Strategic Reasoning at the Lorentz Center in Leiden;
together with Johan van Benthem and Sujata Ghosh.

2011: Reasoning About Other Minds in Groningen; together with Jan van Eijck.
The proceedings of Reasoning About Other Minds are online.

2010: Formal Theories of Communication at the Lorentz Center in Leiden; together with Johan van Benthem and Ram Ramanujam.

2008: Twentieth European Summer School in Logic, Language and Information (ESSLLI) in Hamburg.

2004: Sixteenth Belgium-Netherlands Conference on Artificial Intelligence (BNAIC) in Groningen.

2003, 2006, 2007, 2009: Formal Approaches to Multi-agent Systems (FAMAS'03, FAMAS'06, FAMAS'007, FAMAS'09); together with Barbara Dunin- Kęplicz.