We are pleased to present this special issue of JIOHS, which focuses on optical technologies in the study of tissues and biological liquids. The selected papers were presented during Saratov Fall Meeting — XII International School for Junior Scientists and Students on Optics, Laser Physics and Biophotonics (September 23–26, 2008, Saratov, Russia) in the framework of the following workshops: “Optical Technologies in Biophysics and Medicine,” “Nanostructures and Nanoparticles,” “Microscopic and Low-Coherence Methods in Biomedical Applications,” and “Internet Biophotonics.” All eight papers in this special issue are research papers.