The National Agricultural Library’s Aquaculture Information Center has developed an expert-system based Advisor for supporting reference-related inquiries. The system was created to help improve access to basic resource tools and information in aquaculture, one of the rapidly expanding disciplines within agriculture. System developmental stages are described, including the selection of software and determination of types of information to incorporate into the system. Data distribution is discussed in terms of user groups and feedback mechanisms. The basic expert advisory system was enhanced and linked to external programs, including bibliographic databases through remote access and CD-ROMs. Future projections include external linkage to full-text files and images on laser videodiscs and CD-ROMs. Cooperative updating is encouraged as a means to facilitate the universal role of libraries and information services to disseminate information.