Many of the methods and models so far developed for database schema design have proved to be complex, highly theoretical in nature, and often have NP complete aspects. The method investigated in this project [Smith 1985] is a heuristic to these more formal methods. It is a simple diagrammatic technique and requires little relational theory, yet it is capable of delivering good results. Smith's method in its original form has a number of deficiencies. I have developed solutions to these and implemented them in an application for the Apple Macintosh. The application exhibits features such as "What if?" scenarios, complexity and information management and allows a smooth merging with traditional record-based design methods.