Just as important as *how* to do object oriented programming in the WordPress plugin environment is the question of *why.* In this talk Mike Toppa will use straightforward code examples to explain how to approach OO design for WordPress plugins, and the advantages it provides for maintaining, extending, and testing your code. Mike will give an introduction to 2 foundational principals of good OO design: the Single Responsibility Principle, and the Dependency Inversion Principle.