Invited presentation “Challenges of realising scalable open education with (peer) feedback“. Open HPI Forum, 28.11.2019. Potsdam, Germany.

Invited presentation (online) “MOOCs for (global) sustainable development education. Experiences from the MOOC on Marine Litter”. Presentation provided in the context of the course on open online education of the International Training Centre of the International Labour Organisation (ITC ILO). 25.11.2019.

Invited presentation and workshop “Medienkompetenz. Ein Konzept im Wandel”. 8. Ludwigshafener Bildungsgespräche: Future Skills?! Wie Hochschulen ihre Studierenden im Umgang mit Medien und Daten fit machen können. 7.11.2019. Hochschule für Wirtschaft und Gesellschaft. Ludwigshafen, Germany.

Invited presentation “Perspektiven der Hochschulbildung im digitalen Zeitalter”. Tag der Lehre, 28.06.2019, Fresenius Hochschule, Idstein, Germany.

Invited presentation (online) “The scalability challenge: what higher education can learn from MOOCs and open courses“ CATEDRA EUROPA 2019 conference, 22 March 2019, Universidad del Norte, Barranquilla, Colombia.

Invited presentation 14th CHAIS conference for the study of innovation and learning technologies: learning in the technological era. 13. Februar 2019, Open University of Israel. Ra’anana, Israel

Invited presentation “SchnOERzeljagden, Landkarten und MOOCs: Wem nutzt Open Education? Eine kritische Reflexion zu den Irrungen und Wirrungen der Open Education Bewegung“, 13. September 2018 GMW/E-LEARN NRW 2018. Essen, Germany.

Invited presentation DELFI 2018 “Digitalisierungswahnsinn oder Nebeneffekte des Mainstream?”, 12 September 2018, University of Frankfurt, Germany.

Invited presentation “The structuration of open education”, 21. Juni 2017, University of Valladolid, Valladolid, Spain.

Invited presentation Moving Africa towards Sustainable Security and Peace. 25 – 26 May 2017. Tangaza University College. Nairobi, Kenia.

Invited presentation training week of the SCORE2020 project. 14 December 2016, UNED, Madrid, Spain.

Invited presentation World University Network E-Learning Conference and Community Building for PhD Students, 4 April 2016, Maastricht, The Netherlands.

“Von offenen Lernressourcen zu offenen Lernpraktiken”. Fachforum Open Educational Resources. 1 March 2016, Berlin, Germany.

“MOOCs and Open Education. Increasing access and flexibility for medical education”/ Annual meeting of the Dutch Association for medical education. Heerlen, The Netherlands. 16 November 2015.

Who let the drop out? An alternative perspective on completion in open education”. Presentation provided during the EADTU Annual “Online, Open and Flexible Higher Education Conference”, Hagen, Germany. 29 October 2015.

“Towards a research agenda for open education”. Invited keynote for the annual meeting of the LDE Centre for Education and Learning. TU Delft. 2 October 2015.

“OER Repositorien: Erfahrungen aus internationaler Perspektive. Invited presentation for feasibility workshop on establishment of a German national OER repository. 27 August 2015. University Duisburg-Essen, Germany.

Creating meaning and authenticity with mobile serious learning games”. Keynote presentation at Research & Innovation Week, University of South Africa, Pretoria, South Africa. 5 March 2015 (via video streaming).

“Energy Conservation Behaviour Toolkit”. Presentation given at the symposium “Groene ICT en Duurzame ontwikkeling: Meters maken in het Hoger Onderwijs”, 31 Januar 2013. Driebergen, The Netherlands.

Invited presentation “Digitale Anreizstrukturen”. Presentation during the OpenTransfer Workshop, Berlin, Germany: Bügermut Foundation. 29 November 2012.

Invited presentation “Tablet computers and eBooks in Higher Education” during the 10th eLearning days at the University Koblenz-Landau. 12. June 2012.

Invited presentation “Tablet computers and eBooks for law students at OUNL: Insights from a recent pilot study” during the workshop on Learning in Context, Brussels, 26.03.2012.

Invited presentation. Tablet computers and eBooks. Unlocking the potential for personal learning environments? Invited presentation during the annual conference of the European Association for Distance Learning (EADL), Noordwijkerhout, The Netherlands.

Invited presentation “Schule und Medien 2012. Potenziale und Aussichten”. Invited presentation during the media-concept day at the Otto-Hahn-Gynasium, Bergisch-Gladbach, Germany.

Invited presentation “Peer review – Why does it matter for your academic career?” Presentation provided in the context of the Young Researchers Special Issue 2012 of the International Journal of Technology-Enhanced Learning (IJTEL).

Invited presentation “Orchestration of TEL proposals for the European Framework Program”. Presentation given during Research Away Days of the University College Cork, Rosscarberry, Ireland: UCC.

Invited presentation “Lifelong mobile learning: Increasing accessibility and flexibility with tablet computers and ebooks.” Presentation provided during the opening ceremony of the iPad pilot for schakelzone rechten, Utrecht, The Netherlands.

Invited Lecture ‘Structuration of Personal Learning Environments’. Knowledge Media Institute (KMI), The Open University, Milton-Keynes, UK, July 14, 2011

Demonstration “Open Content for Business and Management Education: OpenScout” at the Online Educa, Berlin, Hotel InterContinental, December 1 – 3, 2010

Invited Presentation at the ICT meeting of the Dutch Educational Research Association (VOR). Structuration of Personal Learning Environments. Utrecht, 30.11.2010.

Invited Presentation “Personal Learning Environments in Black and White”, Workshop “Informal learning and the use of social software in veterinary medicine” of the Network of Veterinary ICT in Education, Utrecht, The Netherlands, 22.01.2010.

Presentation “Semantic Services for Personalised Learning and Formative Feedback” at the Online Educa Berlin 2009, Hotel InterContinental, December 2 – 4, 2009

Invited Workshop “Development of Open Educational Resources” during the conference “Networks, Communities & Learning: Show that you share!” organized by the Bazaar project and the Institute of Education of Utrecht University on the 14th of December 2007.

Invited Workshop Creation and support of Open Educational Resources with Open Source Wikis. 3rd Edumedia Conference 2007. Open Education enhanced by Web 2.0!?!” – Open Educational Practices and Resources for Lifelong Learning.

Invited Talk “Social Software für das technologiegestützte Lernen: Blogs & Wikis”. eLearning day TU Kaiserslautern 2006.

Invited presentation “Supporting Competency Development and Lifelong Learning with Open Source ePortfolios”. Online-Educa Berlin 2005:  Track on Open Content and Open Source Solutions.

Pre-Conferene-Workshop “eLearning: Didaktik und Werkzeuge” (with Peter Baumgartner) in conjunction with the Annual Conference of the Society for Media in Science 2004.