Microsoft Excel can be much more than just a spreadsheet. It has become a development platform in it own right. Applications written using Excel are part of many corporations' core suites of business-critical applications. In spite of this, Excel is too often thought of as a hobbyist's platform. While there are numerous titles on Excel and VBA, until now there have been none that provide an overall explanation of how to develop professional-quality Excelbased applications. All three authors are profesional Excel developers who run their own companies developing Excel-based apps for clients ranging from individuals to the largest multinational corporations. In this book they show how anyone from power users to professional developers can increase the speed and usefulness of their Excel-based apps.