In this paper we suggest a computational model for the 3-D interpretation of a 2-D view based on contour classification and contour interpretation. We concentrate on those contours arising from discontinuities in surface orientation. We combine a generic surface description well suited for visual tasks with a model of the image formation process in order to derive image contour configurations that are likely to be interpreted in terms of surface contours. Next we describe an algorithm which attempts to interpret image contours on the following grounds. First, an image analysis process produces a description in terms of contours and relationships between them. Second, among these contours, we select those which form a desired configuration. Third, the selected contours are combined with constraints available with the image formation process in order to be interpreted in terms of discontinuities in surface orientation. As a consequence, there is a dramatic reduction, in the number of possible orientations of the associated scene surfaces.