A microcomputer system has been developed for collection and analysis of morphometric data from video images of histological sections. Microscopic fields of view are visualized on a video monitor and are overlaid with computer‐generated graphics by means of a video mixer. Planimetric data are entered by drawing on a digitizing tablet while observing the drawn image superimposed on the tissue. Programs are available to calculate various geometric parameters, count objects in a field, perform descriptive statistics, and measure volume and surface area of a solid from a series of cross sections. A program for point‐counting stereology presents single points for scoring within a user‐defined reference area. The potential applications of interactive graphics in morphometry are discussed. Copyright © 1986 Wiley‐Liss, Inc.