Abstract
The stereological procedures available for estimating volume, surface area and number of the structural components of cells and tissue are reviewed. The applications of stereology to the study of liver, mammary gland, lung and placenta are discussed with particular emphasis on the aspects of interest to veterinary pathologists. Stereology provides the cell biologist and the pathologist with a powerful tool for describing biological structure in quantitative terms at various levels of organization from the organ to the organelle.