AbstractA review of recent literature indicates that histopathologists continue to be worried by problems of interobserver and intraobserver variations in the diagnoses of histological specimens. It is suggested that quantification would go a long way toward solving some of these problems. The basic ideas of stereology are discussed and illustrated by worked examples. Recent applications of stereology to histopathology are given. The problems of sampling and other difficulties are commented upon. A role for the histotechnologist is suggested.