This book includes the post-conference proceedings of the 20th RoboCup International Symposium, held in Leipzig, Germany, in July 2016. In addition to the 38 contributions to the symposium, selected from 63 submissions, the book also contains 15 champion papers of teams winning individual leagues of the RoboCup 2016 competition, the Amazon Picking Challenge, and the Harting Open Source Award. The papers present current research in the fields of robotics and artificial intelligence with a special focus to robot hardware and software, environment perception, action planning and control, robot learning, multi-robot systems, and human-robot interaction.