Are you happy? Could you be happier? Gretchen Rubin was already "pretty happy" when she asked herself these very questions. In search of the answers, she started her own pursuit of happiness, which eventually became a New York Times bestseller titled, The Happiness Project. She has now written a second book, Happier at Home, based on the idea that the home is the foundation of happiness. Knowledge@Wharton recently spoke with Rubin about why happy people work more hours each week, how to make and keep happiness resolutions, how to ward off the three happiness leeches and how to start your own Happiness Project.