The 52 full papers, 11 findings, 42 short papers and 76 papers of other types presented in these proceedings were carefully reviewed and selected from 530 submissions. The accepted papers cover the state-of-the-art in information retrieval and recommender systems: user aspects, system and foundational aspects, artificial intelligence and machine learning, applications, evaluation, new social and technical challenges, and other topics of direct or indirect relevance to search and recommendation.