(2019) ‘The Movement Party – Winning Elections and Transforming Democracy in a Digital Era: Reflections on Paolo Gerbaudo’s Chapter’ in D. Chandler and C. Fuchs (eds) Digital Objects, Digital Subjects: Interdisciplinary Perspectives on Capitalism, Labour and Politics in the Age of Big Data, London: University of Westminster Press, pp. 199-204.
(2018) ‘Connective or Collective? The Intersection between Online Crowds and Social Movements in Contemporary Activism’ in G. Meikle (ed) The Routledge Companion to Media and Activism, Routledge, pp. 108-116.
(2018) with Poell, T. and Rajagopalan, S. ‘Publicness on Platforms: Tracing the mutual articulation of platform architectures and user practices’ in Papacharissi, Z. (ed) A Networked Self: Platforms, Stories, Connections. New York: Routledge, p.. 43-58.
(2017) with Orsalia Dimitriou ‘Protest Spaces Online and Offline: The Indignant Movement in Syntagma Square’ in G. Brown, A. Feigenbaum, F. Frenzel and P. McCurdy (eds) Protest Camps in International Context: Spaces, Infrastructures and Media of Resistance, Bristol and Chicago: Policy Press, pp. 71-90.
(2016) with Lappas, G., Triantafillidou, A., Yannas, P., Kleftodimos, A. and Vasileiadou, O. ‘Social Media Battles: their Impact during the 2014 Greek Municipal Elections’. Journal of Universal Computer Science 22(3): 375-393.
(2015) Creating the collective: social media, the Occupy movement and its constitution as a collective actor. Information, Communication and Society 18(8): 872-886. [Special Issue on ‘Social Media and Protest Identities’ edited by P. Gerbaudo and E. Trere]
(2014) ‘Transnational Civil Society and Social Movements’ in Wilkins, K.G., Tufte, T. and Obregon, R. (eds) Handbook of Development Communication & Social Change, Wiley-Blackwell.
(2013) ‘Internet cultures and protest movements: the cultural links between strategy, organizing and online communication’ in B. Cammaerts, A. Mattoni and P. McCurdy (eds) Mediation and Social Movements, Bristol: Intellect, pp. 75-94.
(2010) ‘Email lists and participatory democracy in the European Social Forum’. Media, Culture & Society 32(3): 355-372.
(2010) ‘Between Individuality and Collectiveness: Email Lists and Face-to-Face Contact in the Global Justice Movement’. In Calderaro, A. & Livermore-Romm, C. (Eds.) “E-Politics in a Global Context”, Special Issue. International Journal of E-Politics 1(1): 41-56.
(2010) ‘Activism Transforms Digital: The Social Movement Perspective’ in M. Joyce (ed.) Digital Activism Decoded: The New Mechanics of Change, New York & Amsterdam: International debate education association, pp.101-118.
(2010) (in Greek) ‘The Role of the Internet in Current Global Activism’ in S. Papathanasopoulos (ed.) Communication and Society from the Twentieth to the Twenty-first Century (Fourth Edition). Athens: Kastaniwtis.
(2009) ‘Email lists and the construction of an open and multifaceted identity: The case of the London 2004 European Social Forum’. Information, Communication and Society 12(6): 817-839.
(2009) ‘Decentralization and Communication: Email Lists and the Organizing Process of the European Social Forum’ in A. Karatzogianni (ed.) Cyber Conflict and Global Politics, London: Routledge, pp. 188-204.
(2009) ‘Collective Action and the Social Web: Comparing the architecture of Avaaz.org and Openesf.net’ in N. Carpentier, P. Pruulmann-Vengerfeldt, R. Kilborn, T. Olsson, H. Nieminen, E. Sundin and K. Nordenstreng (eds) Communicative approaches to politics and ethics in Europe, Tartu: University of Tartu Press, pp. 129-140.
(2008) ‘Decision-making online and offline: The case of the ‘movement for alternative globalization’ in N. Carpentier, P. Pruulmann-Vengerfeldt, K. Nordenstreng, M. Hartmann, P. Vihalemm, B. Cammaerts, H. Nieminen and T. Olsson (eds.) (2008) Democracy, Journalism and Technology: New Developments in an Enlarged Europe, Tartu: University of Tartu Press, pp. 217-228.
(2005) ‘Exploring the Role of the Internet in the “Movement for Alternative Globalization”: The case of the Paris 2003 European Social Forum’. Westminster Papers in Communication and Culture, 2(1): 72-95.
(2005) ‘Civil Society Organizations and the Internet: the Case Studies of Oxfam, Amnesty International and the World Development Movement’ in W. de Jong, M. Shaw and N. Stammers (eds) Global Activism, Global Media, London: Pluto Press and Ann Arbor: University of Michigan Press, pp. 208-222.
(2005) Book Review of ‘Contesting Media Power: Alternative Media in a Networked World’ by Couldry N. and Curran J. (eds) in Soundings: A Journal of Politics and Culture (31): 111-114.
(2004) Book Review of ‘The Internet Revolution: A Global Perspective’ by Giovanetti E., Kagami M., and Tsuji M. (eds) in Trends in Communication, Vol.12(1): 63-64.