Three fundamental problems in computer vision are addressed in this dissertation. The first deals with the problem of how to extract and assemble a rich symbolic representation of the gray level intensity changes in an image. Results show that the facet model based feature extraction scheme proposed here is superior to the other existing techniques. The second problem addressed deals with the interpretation of the resulting structures as three-dimensional object surfaces. The three different shape modules described in this dissertation are found to be useful in the recovery of intrinsic scene characteristics. Finally, mechanisms for interaction among different sources of information obtained from different shape modules are studied. It is demonstrated that interactions among shape modules can enhance the data acquired by different means.