This study used in-depth interviews with pairs of mother-and daughter-in-law from 38 households in Taipei and Tao-Yuan counties in Northern Taiwan to examine the relation between in-group/out-group status and relationship valence. Mother-and daughter-in-law who take each other into their own circle and treat each other as an in-group member tend to have good relationships. In contrast, mother-and daughter-in-law who treat one another as outsiders have distant relationships. A critical factor affecting the relationship between mother-and daughter-in-law is whether or not they take each other into their inner circle.