This project involved the development of N-S Chart; a NassiShneiderman Cartographer for the Apple Macintosh. N-S Chart is a tool for drawing and maintaining Nassi-Shneiderman diagrams, and incorporates the beneficial features of diagramming methods, and automated computer graphics tools discussed in chapters 2 and 3. The features of N-S Chart are discussed in chapter 7. Nassi-Shneiderman charts (N-8 Charts), an alternative to the flowchart, are described in chapter 5. A cartographer is someone who works with charts. In the process of implementing the original Nassi-Shneiderman diagramming technique, modifications and improvements to the method were developed and implemented. Flowcharts were designed in the days of 2nd generation languages. They do not support the constructs used in todays 3GLs and 4GLs. NassiShneiderman charts do. However the original Nassi-Shneiderman diagrams did have a few drawbacks which prevented them from becoming more widely used than they have been. The problems of data specification and drawability have been addressed in this project and successful solutions have been found. Chapter 8 describes aspects of user interface design. Symbols have been added to the drawing technique to support the specification of data inputs and outputs. Symbols have been modified to clarify charts and the drawing and maintenance process has been automated and simplified to an almost trivial level. Details of the implementation of N-S Chart are discussed in chapter 9 and possibilities for further extension are mentioned in chapter 10.