It is now well established that all living systems emit a weak but permanent photon flux in the visible and ultraviolet range. This biophoton emission is correlated with many, if not all, biological and physiological functions. There are indications of a hitherto-overlooked information channel within the living system. Biophotons may trigger chemical reactivity in cells, growth control, differentiation and intercellular communication, i.e. biological rhythms. Biophotonics is becoming one of the most fashionable fields in modern science and biotechnology. Biophotonics and Coherent Systems in Biology an account of the original papers presented by the participants of the 3rd Alexander Gurwitsch Conference on the Biophotonics and Coherent Systems in Biology, Biophysics and Biotechnology which took place in Tauric University (Crimea, Ukraine) September 27 October 1, 2004.