Dear Friends and Colleagues, We are organizing a stream on Network Optimization and Social Networks at the forthcoming EURO conference in Valencia, July, 8-11, 2018. We would like to cordially invite you (or one of your co-authors) to submit an abstract to this stream. To do so, please visit: https://www.euro-online.org/conf/euro29 and use one of the following invitation codes depending on the topic of your presentation: * Social network analysis (invitation code: aa30f1b1; session chaired by Mario Ruthmair) * Robust optimization (invitation code: dde3ab81) * Other methodological and / or  application oriented contributions to network design and network optimization (invitation code: 5d6fa58b) If you would be willing to even organize a full session of 3-4 papers, please contact us! Apologies for cross-postings and best regards, Christina Büsing and Markus Leitner -- Markus Leitner Department of Statistics and Operations Research http://isor.univie.ac.at Vienna Center for Operations Research http://vcor.univie.ac.at University of Vienna Oskar-Morgenstern-Platz 1, 1090 Vienna, Austria Phone: +43-1-4277-38662 http://homepage.univie.ac.at/markus.leitner