When people live and work together closely and have a common history they begin to share basic assumptions about the way things are and, indeed, should be (e.g., whether children should work, whether people should marry for love, or whether children should sleep with their parents) (Schweder et al., 1998). These shared assumptions also concern what the best, or most admirable, personality traits are-in general and for certain subgroups within a society

In this chapter, I suggest a goodness-of-fit model that builds on previous models (Lerner, 1983; Lewis, 1987). I suggest that, in any given culture, there are both psychological and practical features of the environment that reflect people’s shared assumptions about behavior. As a result, the environment favors some temperamentally based behaviors over others, and the favored behaviors are then more likely to be associated with good developmental outcomes. I draw examples of the various links in this model from the literature on shyness, inhibition, and anxiety, and compare findings from two studies of the life courses of shy people: one using an American sample (Caspi, Elder, & Bern, 1988) and the other using a Swedish sample (Kerr, Lambert, & Bem, 1996).