This is the third in a series of videos which introduce object oriented programming (OOP) using Visual Basic.NET (VB.NET). This video demonstrates how to write property procedures within a class. It also explains the potential benefits of taking this approach rather than simply declaring public variables, namely, that it is possible to validate property values while they are being assigned. This video also demonstrates how Visual Studio can be used to debug a Windows Forms Application that references class libraries. Specifically, how Visual Studio can be configured to allow stepping through the code inside a Class Library project when the application is launched from a project that references the library. Later videos in the series will cover constructors, method overloading, inheritance and method overriding.