This book constitutes the proceedings of the 4th International Workshop on Symbiotic
Interaction Symbiotic 2015 held in Berlin Germany in October 2015. The 11 full papers and 8
short papers presented in this volume were carefully reviewed and selected from 23 submissions.
The papers present an overview of the symbiotic relationships between humans and computers as
well as novel advancements. The idea of symbiotic systems put forward in this workshop
capitalises on the computers' ability to implicitly detect the users goals and
psycho-physiological states and thereby enhancing human-computer interaction (HCI). A special
focus of this year's Symbiotic Workshop will be on physiological computing approaches e.g.
using brain-computer interface (BCI) technology.