Three-dimensional object shape and orientation are determined from a single perspective view with very little a priori knowledge. Groups of parallel lines are detected by searching for common vanishing points, and the orientation of a group of parallel lines is determined by the location of its vanishing point. Edge contour traces are made for finding a primary face of the object. A least-slant-angle heuristic is adopted to help find the orientation of the primary face. A model of the 3D object is constructed in steps, beginning with the primary face. The shape and orientation of the faces in the model are adjusted iteratively so as to minimize the discrepancies between the object image and the image generated by the model. Three examples are presented, and the resulting 3D model interpretation of the object is consistent with human perception.