The 3D shape of live animals plays an important role in achieving good husbandry and in selecting breeding stock. Many shape features are subtle and cannot be extracted from 2D images. With 3D data, it would be possible to extract cross-sectional areas and volumes, and to measure features such as the squareness of the back muscles, which are known indicators of lean muscle mass (Whittemore 1998). However, there is currently no simple method to measure 3D shape in live animals. In this work a system has been developed for freezing the motion of a pig using flash photography and processing the images to extract the 3D surface shape. The imaging system is based on stereo photogrammetry. Three stereo pods, each consisting of two digital cameras, were set up at perpendicular directions in order to cover the whole of a cuboidal imaging volume. The imaging volume dimensions were 1300 mm long × 900 mm high × 700 mm deep. The imaging system was calibrated prior to capturing the pig images. Multiresolution correlation-based stereo matching (Siebert and Urquhart, 1994) was used to establish correspondences between the left and right images in each stereo pair. The output of the stereo matching of each pod was a 2.5D range image. These range images were integrated into a 3D model.