Are you looking for The One? Well, according to Dr Helen Fisher, biological anthropologist and relationship expert, you don't have to look any further for the way to find that special someone than your very own brain chemistry. Based on Dr Fisher's groundbreaking personality type study, in which she analyzed the personalities of more than 28,000 people, Why Him? Why Her? provides a formula for long-term love that is based on cutting-edge discoveries in evolutionary neurology. Once you've identified yourself as one of the personality types (explorer, builder, negotiator, or director) Dr Fisher provides a detailed plan of how to find, fix, or keep up your ideal love match.