Chapters 1 and 2 have considered psychologists’ ideas about the nature of happiness and their procedures to measure its two main components, labeled here as subjective well-being and self-validation. The book’s primary question was identified as “Why are some people at work happier or unhappier than others?” and answers to that question have been seen to require an understanding not only of the environment but also of the person. We now move on to consider variables in those two domains.