Presently there is a trend in manufacturing system design from stand-alone, automatic operations to Computer Integrated Manufacturing (CIM). The success of the integration depends largely on the performance of system control software. This document presents research in the design and implementation of a shop control system, for a CIM facility, using a new method called the three-layer integrated approach. Two basic techniques used in this research are expert systems and object-oriented programming. The CIM system at VPI is an automated manufacturing and assembly system. In designing the control system for this CIM facility, the design of products, production facilities, and overall system must be taken into account. In order to manage this complex system, a control system called the “shop controller” has been developed using C++, an object-oriented programming language. In addition, three real-time simulators for the cell controllers have been developed for testing and debugging the production rules of the expert system. The basic approach taken for the shop control system has several advantages: applied intelligence, program efficiency, reusability of code, and ease of maintenance. Moreover, this approach has a new feature—modularity, which is the result of combining expert systems and object-oriented programming. / Master of Science