No one can deny that Netflix has changed the way we watch movies and TV shows. In some studies, Netflix traffic accounts for roughly a third of all bandwidth used on the Internet. With such a well known service, how do they approach testing and improving their product design? In this talk, Anna Blaylock from the Netflix Design Team shares a detailed overview of the design testing process at Netflix. Anna looks at how Netflix encourages new people to join the service, and how it becomes increasingly personalized as you use it.