This book reviews the most recent developments of fluorescent imaging techniques for medicinal chemistry research and biomedical applications, including cell imaging, in vitro diagnosis and in vivo imaging. Fluorescent imaging techniques play an important role in basic research, drug discovery and clinical translation. They have great impact to many fields including chemical biology, cell biology, medical imaging, cancer diagnosis and treatment, pharmaceutical science, among others, and they have facilitated our understanding of diseases and helped to develop many novel powerful tools for imaging and treatment of diseases. This book will appeal to scientists from numerous fields such as chemistry, pharmaceutical science, biology, materials science, and medicine, and it will serve as a very useful and handy resource for readers with different levels of scientific knowledge, ranging from entry level to professional level.