This study investigates sex differences in nonresident parents' level of contact with biological children with whom they do not live. With data from the 1987-1988 National Survey of Families and Households, I assess social contact using nonresident parents' own reports of frequency of telephone calls and letters, in-person visits, and extended visitation. Multivariate results show that nonresident mothers and fathers are similar with respect to in-person visits, but mothers exhibit higher levels of telephone and letter contact and extended visitation. These results suggest that nonresident mothers' and fathers' relative frequencies of involvement with their absent children are not as straightforward as previously thought. Although traditional gender roles may encourage greater contact between nonresident mothers and absent children on some dimensions of contact, results suggest that nonresident mothers and fathers may encounter circumstances that make frequent in-person contacts with absent children difficult to maintain. Key Words: gender differences, noncustodial, nonresident, parenting, visitation. A consequence of increased divorce and nonmarital childbearing is that roughly half of all children will live apart from at least one biological parent during some part of their childhood (Bumpass & Sweet, 1989a). Since the tender years doctrine of the 1800s until quite recently, mothers have nearly always retained custody of the children following divorce (Luepnitz, 1982). However, child custody decisions, now based on the best interests of the child rather than the parent's sex (Maccoby & Mnookin, 1992), are gradually altering the composition of resident and nonresident parents. About 1.6 million or 14% of custodial parents are now men (Scoon-Rogers & Lester, 1995), the result of never-married and divorced fathers increasingly receiving physical custody of their children (Garasky & Meyer, 1996). At the same time, the number of noncustodial mothers in the United States has grown to roughly 1 million (Herrerias, 1995). Previous empirical studies of nonresident parenting do not reflect these trends. First, what we know about nonresident parents' contact with children is based almost entirely on children with nonresident fathers (Furstenberg & Nord, 1985; Furstenberg, Peterson, Nord, & Zill, 1983; King, 1994; Mott, 1990; Seltzer & Brandreth, 1994). Studies using nationally representative data consistently find that father involvement with nonresident children is extremely low-a large proportion of children see their fathers infrequently or not at all. Nonresident fathers' pattern of disengagement from biological children has been explained by men's tendency to view marriage and child care as an inseparable role-set based on coresidence (Furstenberg, 1990; Furstenberg & Cherlin, 1991). However, despite their growth as a proportion of all nonresident parents, a comparable body of empirical research does not exist for nonresident mothers. Information about nonresident mothers comes mainly from small and highly select samples of women (Christensen, Dahl, & Rettig, 1990; Greif & Pabst, 1988; Herrerias, 1995). As a result, we know little about the sociodemographic characteristics of nonresident mothers, their level of involvement with absent children, or how the characteristics of nonresident mothers affect contact. A second issue is that sex differences in social ties with absent children remains unresolved. Nonresident mothers are considered to be more highly involved nonresident parents than are nonresident fathers. Indeed, high levels of contact between children and nonresident mothers is often suggested as an explanation for resident stepmothers' greater difficulty with stepchildren (Clingempeel & Segal, 1986; Furstenberg & Nord, 1985). Yet empirical evidence of nonresident mothers' level of involvement with absent children, compared with the level of nonresident fathers, is actually quite weak. …