Calcium phosphates are key materials to sustain life on Earth as constituent of the gravity-defying bony skeletons of all vertebrates as well as the dentine and enamel materials of teeth. This book contains accounts on the historical development of the scientific knowledge gained on calcium orthophosphates, the latest information on the structure of carbonate-bearing hydroxyapatite, the role played by small amounts of molecular water residing in synthetic hydroxyapatite and bone mineral, as well as the nature of oxyhydroxyapatite and oxyapatite as intermediates during dehydroxylation of hydroxyapatite, pertinent information to unravel the complex processes relevant for plasma-sprayed calcium phosphate coatings on endoprosthetic implants. This book is recommended to industrial and academic professionals in the fields of medical technology, orthopedy, dentistry, biology, materials science, chemistry, environmental engineering, and mineralogy.