This special issue is devoted to Smart Systems. It has been an exciting opportunity to collect together papers mainly from authors who were invited to present talks at the 3rd International Conference of Smart Systems Engineering 2015, October 8–9, 2015. The conference place was the 100th Anniversary Hall, Faculty of Engineering, Yamagata University, Yonezawa, Japan. This conference attracted scientists and researchers from all over the world, who presented and discussed the challenges and emerging technologies in the smart materials, devices, and systems.

We would like to thank Prof. Tomoya Higashihara (SmaSys 2015, conference chair), all the organizing committee members, specially iFront staff and students for their effort to make this conference and special issue a success.

We would like to acknowledge the sponsors of the conference: Japan Society for the Promotion of Science (JSPS), The Society of Polymer Science, Japan (SPSJ), Life-3D Printing Innovation Center (LPIC), Yamagata University, Soft and Wet Matter Engineering Laboratory (SWEL), Total Assistance for Seasonal Foods Transportation from Yamagata (TASTY) Program, Alumni Association of Yamagata University, Yonezawa Convention Bureau, and Graduate School of Science and Engineering, Yamagata University.

We would like to thank Venkat Ganesan from Microsystems Technologies Journals Editorial Office, for his assisting in making this special issue a success.

We look forward to your participation in future special issues of Smart Systems.

Sincerely,

Guest Editors

Prof. Ajit Khosla

Prof. Hidemitsu Furukawa

Prof. Bernd Michel

Editor-in-Chief. Microsystem Technologies