Book excerpt: Calcification in Biological Systems provides a collection of up-to-date papers regarding calcification in a variety of biological systems. The papers are not simple reviews of the literature. Each paper reflects the personal experience of the author(s) and is rich in constructive criticism and suggestions. Topics range from basic molecular processes to general structural problems in systems as different as unicellular organisms and human skeletal tissues. Because calcification is so diffuse in the animal kingdom, this book makes no attempt to achieve a conclusive synthesis of available results and current ideas. Instead, its merit lies in its ability to be useful to investigators with different scientific backgrounds and areas of interest.