The ACM Recommender System conference is the premier international forum for the presentation of new research results, systems and techniques in the broad field of recommender systems. Recommendation is a particular form of information filtering, that exploits past behaviours and user similarities to generate a list of information items that is personally tailored to an end-user’s preferences. The seventh conference in this series, RecSys 2013, will bring together researchers and practitioners from academia and industry to present the latest results and identify new trends and challenges in providing recommendation components in a range of innovative application contexts. As RecSys brings together the main international research groups working on recommender systems, along with many of the world’s leading e-commerce companies, in the last number of years, it has become the most important annual conference for the presentation and discussion of recommender system research. In addition to the main technical track, RecSys 2013 program will feature keynote and invited talks, tutorials covering state-of-the-art in this domain, a workshop program, an industrial track and a doctoral symposium. Published papers will go through a rigorous full peer review process. The conference proceedings, which are available both as bound volume and via the ACM Digital Library, are expected to be widely read and cited. ACM RecSys 2013 will take place at the City University of Hong Kong from Oct 12-16, 2013.