The development of a software package is a complex and time consuming process. Computer Assisted Software Engineering (CASE) tools, such as Excelerator, DesignAid and SA Tools have offered an alternative to the traditional methods of system design. While the use of these design tools can lessen the burden of project management, there currently exists no systematic method for describing or evaluating existing products.This study identifies criteria for software development tools by examining three products used in a PC-based computing environment. The three software development tools studied are DesignAid version 4.0 by Nastec Corporation, SA Tools by Tekcase Corporation, and Excelerator version 1.7 by Index Technology Corporation. In order to give the "look and feel" of the products, the same design project is implemented on each of the tools. Then each product is evaluated with respect to a given set of criteria.