Since the publication of the first edition of the Handbook in 2002, optical methods for biomedical diagnostics have developed in many well-established directions, and new trends have also appeared. To encompass all current methods, the text has been updated and expanded into two volumes. Volume 1: Light - Tissue Interaction features eleven chapters, five of which focus on the fundamental physics of light propagation in turbid media such as biological tissues. The six following chapters introduce near-infrared techniques for the optical study of tissues and provide a snapshot of current applications and developments in this dynamic and exciting field. Topics include the scattering of light in disperse systems, the optics of blood, tissue phantoms, a comparison between time-resolved and continuous-wave methods, and optoacoustics.