· 2011: Maître de conferences invité at École Centrale de Marseille, Marseille, France.
· 2011: Research grant for visiting the Slovakian Academy of Sciences offered by the Ministries of Education of Greece and Slovakia (Bilateral Exchange Programme for Researchers).
· 2006 - 2007: Post-doctoral researcher at the McMaster School of Computational Engineering and Science, McMaster University, Hamilton, Ontario, Canada. Supervisor: Assist. Prof. George Karakostas (see my oldweb page).
· 2006: Post-doctoral researcher at the Laboratoire Bordelais de Recherche en Informatique (LaBRI), Bordeaux, France. Supervisors: Dr. Ralf Klasing, Prof. Andre Raspaud.
· 2004 – 2006: Post-doctoral researcher at the Department of Informatics and Telecommunications, National and Kapodistrian University of Athens, Athens, Greece. Supervisor: Prof. Ioannis Emiris.
· 2003 – 2004: Post-doctoral researcher at the Research Chair in Distributed Computing, Département d'informatique et d'ingénierie, Université du Québec en Outaouais, Gatineau, Québec, Canada. Supervisor: Prof. Andrzej Pelc.