> Head, Department of Chemistry & Pharmaceutical Sciences - since Feb 2019
> Head, Division of Theoretical Chemistry - since 2010
> Chairman of the Board, Holland Research School of Molecular Chemistry (HRSMC) - since 2010
> Member, NWO Table Chemistry
> Editorial Board member, Chemistry - An Asian Journal (VCH and ChemPubSoc Europe)
> Editorial Board member, Chemistry - A European Journal (VCH and ChemPubSoc Europe)
> Editorial Board member, ChemistryOpen (VCH and ChemPubSoc Europe)
> Editorial Board member, Physcial Chemistry Chemical Physics (Royal Society of Chemistry)
> Editorial Board member, Journal of Computational Chemistry (Wiley)
> Chairman, Program Committee, BSc Scheikunde (undergraduate program) & MSc Chemistry (graduate program), Vrije Universiteit Amsterdam & University of Amsterdam
> Member, Scientific Advisory Board - Institute of Computational Chemistry and Catalysis (ICCC), University of Girona
> Member, Advisory Board - Leiden Institute of Chemistry (LIC), Leiden University
> Membership of Chemical Societies: (1) KNCV (Netherlands), (2) GDCh (Germany), (3) ACS (USA), (4) IUPAC (international), (5) WATOC (international), (6) AGTC (Germany)
> Referee for Funding Agencies, i.a.: (1) NWO, Netherlands; (2) ERC, EU; (3) NSF, USA, (4) FWF, Austria; (5) RCN, Norway; (6) NSERC, Canada; (7) Petroleum Research Fund (PRF), USA; (8) U.S. Department of Energy (DOE), USA; (9) Portuguese Foundation for Science and Technology (FCT); (10) The Croucher Foundation, Hong Kong, China; (11) Academy of Finland, Finland; (12) National Research Foundation (NRF), South Africa; (13) New Eurasia Foundation (NEF) & Ministry of Education and Science, Russia; (14) Fonds Wetenschappelijk Onderzoek (FWO), Belgium. (15) Croatian Science Foundation (CSF); (16) Swiss National Science Foundation (SNF); (17) Freiburg Institute for Advanced Studies (FRIAS), Germany; (18) Research Council for Natural Sciences and Engineering, Finland; (19) Deutsche Forschungsgemeinschaft (DFG), Germany.
> Referee for 100+ international scientific journals