The second chapter explores the concepts of genetics and personality features and their relevance to psychiatry. This chapter explores aspects of normal and abnormal personality features from theoretical and clinical points of view. The author helps to undo a minor criticism I have with the title of this worthy book, which, in my mind, unintentionally tends to minimize its importance and scope. To many readers, "personality" might suggest the veneer of an individual’s uniqueness in terms of behavior, and an entire book on the genetics of personality may put off potential readers. The first two chapters, as well as others in this book, discuss behavioral traits or behavioral phenotypes as elements of personality and clarify the broader range of the editors’ efforts.