This book contains the refereed proceedings of the 6th Scandinavian Conference on Information Systems, SCIS 2015, held in Oulu, Finland, in August 2015. The theme for this book as well as for the conference is "Design for, with, and by Users." This theme has characterized information systems research for decades, and it is still a vibrant topic, especially so within the Scandinavian tradition. The 16 full papers accepted for SCIS 2015 were selected from 44 submissions. In addition, two keynote extended abstracts and one keynote paper are included.