We examine the key issues in designing an optical expert system architecture. Our conclusions, however, are extendable to architectures for supporting traditional symbolic processing. To determine the basic operations necessary for constructing an expert system, we examine the underlying symbolic processing languages and their associated computational models. We show that traditional symbolic processing in optics would require efficient means of representing and manipulating complex structured data. This requirement necessitates a location-based addressable memory in optics. Based on the analyses of the computational models, we conclude that the architecture most feasible for optical implementation is that for a combinator graph reduction computational model. We briefly outline a proposed fine-grained optical architecture for this computational model.