**Polish Up Your Programs...** Inside this book, you'll find out how to turn your programs into software to be proud of. You'll learn the techniques used by professionals to make their programs "user friendly" and robust enough to keep working all the year round, even in the hands of the most inexperienced users. Numerous examples are presented to illustrate the techniques - including input/output, printer techniques, error trapping, and filing methods. There are also some valuable sections on data security (including the prevention of copying) and program documentation. All listings are in the widely-used BBC BASIC but users of other dialects will find that conversion is straightforward. **...And Profit From The Results!** After you've mastered these techniques, you'll be able to exploit them to the full. There is a ready market for professional software in the business, educational and home environments. You'll be able to offer your programs to software distributors, or even to set up your own software house! **About The Authors** Alan and Sue Rowley run their own software business, and are well known for their many articles in the popular computing press. **About Us** Sigma has published well over a hundred books - and we'd like to hear from new authors in computing, science, electronics and engineering.