- A sample of 352 Bedouin Arab children--174 from monogamous and 178 from polygynous families--participated in this study. The authors used self-reported standardized measures to assess the participants' level of self-esteem, mental health, social functioning, father-child relationships, mother-child relationships, and family functioning. The findings revealed that children from polygynous families reported more mental health and social difficulties as well as poorer school achievement and poorer relationships with their fathers than did their counterparts from monogamous families. In addition, the children from polygynous families rated their families' functioning and economic status as poorer than did those of monogamous families. Thus, the authors suggest that a polygynous family structure negatively affects the family's socioeconomic status and interpersonal relationships and impairs the children's psychological and social functioning. The authors discuss implications for practice and policy.