An expert system is a computer program that analyzes a situation based on available facts and gives recommendations equivalent to an expert's advice. In the Dairy Farm Business Summary (DFBS) Expert System the available facts are DFBS data and the experts are farm management faculty in the Department of Agricultural, Resource, and Managerial Economics. New York dairy farmers and Cooperative Extension Agents and Specialists use the DFBS Expert System as a tool to assist in analyzing the financial and production performance of dairy farm businesses. The DFBS Expert System Version 5.0 is to be used in conjunction with the Dairy Farm Business Summary generated by Micro DFBS Version 3.1.1 The DFBS Expert System is a Lotus 1-2-3 spreadsheet developed by Darwin Snyder, former Research Associate in the Department of Agricultural, Resource, and Managerial Economics. The Lotus 1-2-3 electronic spreadsheet software package (Version 2.2 or later) or compatible software and the Micro DFBS computer program are required to run the DFBS Expert System.