In some respects actinic keratosis is the most common and best-known pathology in dermatology. Being such an ordinary pathology, actinic keratosis gives nevertheless insight into an extraordinary number of important biological and clinical processes. Actinic keratoses are found in significant numbers on the sun-exposed skin of Caucasians, especially those living in sun-bathed countries such as Australia, as two of the editors and a considerable number of the authors of this book do. The authors who have contributed to this volume are researchers and clinicians discussing actinic keratosis across the whole spectrum – from epidemiology to immunology, from molecular biology to behavioral psychology – and of course pathologists and clinicians dealing with patients who experience the many manifestations of actinic keratoses. The fact that all these various aspects are considered renders this book valuable reading for scientists and clinicians alike.