Chlorophylls are the most obvious natural pigments on Earth where they can be observed even from satellites in outer space: they also sustain life on Earth through their involvement in photosynthesis. With 37 authoritative chapters, this book reviews recent progress and current status of studies on the chemistry, metabolism and spectroscopy of chlorophylls, bacteriochlorophylls and their protein complexes. Also discussed is progress on the applications of the chlorophylls as photosensitizers in photodynamic therapy of cancerous tumours, and as molecular probes in biochemistry, medicine,...