Most developers aren’t too excited about developing for Office applications – with good reason: until recently, it involved writing VBA code using an IDE which was top-notch in the early 90’s but hasn’t evolved since. Not any more: since Microsoft introduced VSTO, you can add custom features to Office 2003 and 2007 applications and documents, using .NET languages and Visual Studio 2008. This is a fantastic marketing opportunity for developers. Companies large and small all use Office, and typically have numerous documents automated with VBA, which are crucial to their business. These tend to be large, and hard to maintain and scale. Yet users are often reluctant to move away from the familiar Office environment, and embark into a development process they don’t know well. VSTO is a great way to bridge the gap, and get the best of both worlds. You can start with a working prototype (their document), and refactor it to use .NET technology, while leveraging the familiarity of the Office user experience, and lowering the cost of adoption. In this session, I will share with you my experience developing with VSTO. I will specifically focus on Excel, because it is widely used by finance departments to develop highly automated workbooks.