The Visio Product Team has been working for several years to design, code, test and deliver Visio 2010. It takes lots of coordination and collaboration to develop a complex software application. While there are many roles involved in the engineering process, it is the Program Managers, Developers and Testers that work together the most closely from beginning to end. Program Managers gather customer input and design the features for the release. Developers are the coders responsible for implementation of the software. Testers ensure both high quality and that the capabilities really address the customer scenarios we have targeted.
Microsoft has created a series of videos describing Office 2010 (the full wave of products being released) and some of the roles people play in the engineering process. Here is a video about the engineering behind Visio 2010 from the perspective of the Tester.