Hydroxyapatite is the structural prototype of the main inorganic constituent of bone and teeth and, together with fluorapatite, is also one of the principal minerals in commercial phosphate ores. The adsorption characteristics and surface chemistry of hydroxyapatite are important in understanding the growth, dissolution and adhesion mechanisms of bone and tooth tissues and in elucidating the factors in mineral beneficiation such as floation and flocculation. This volume essentially documents the proceedings of the symposium on the same topic held at the American Chemical Society Meeting in Kansas City, MO, September 12-17, 1982. It includes a few papers which were not presented at the symposium but does not comprise the entire program. This volume provides, on a limited scale, a multidisciplinary overview of current work in the field of adsorptive behavior and surface chemistry of hydroxyapatite and includes certain review articles. There are two papers each on adsorption, adsorption and its effects on crystal growth or dissolution kinetics, effects of electrochemical parameters on solubility and adsorption, and newer physical methods (exoemission and high-resolution NMR) of examining hydroxyapatite surface. There is one paper each on structure modelling of apatite surface based on octacalcium phosphate interface and on biodegradation of sintered hydroxyapatite.