This volume is a practical guide of theranostics using intraoperative fluorescence imaging technology, as an all-out effort by the Japanese Society for Fluorescence Guided Surgery. It describes the various approaches the technique is being used such as vascular imaging, identification of lymphatic vessels by intratissue injection, lymph node imaging, and imaging for identification of anatomical structures. The book is organized into three major parts and the first one delivers the basics, introducing the use of the technology in clinical settings and initial setups. Next comes the description of clinical applications where chapters illustrate perfusion assessment, cancer localization, anatomy visualization, and lymph nodes/ducts mapping. Each chapter is devoted to the specific surgical field and disease areas, presenting images and videos of case studies. The last part presents some upcoming techniques for treatments. The Editor and the authors wish the ideas presented here will behints to bridge the knowledge between surgeons and basic researchers for further innovation and practicality. It is important to stay up-to-date since intraoperative fluorescence imaging has been applied to clinical settings in various surgical fields and at the same time, novel techniques improving the efficacy of the technology have also been developed actively.