In mediating child custody disputes, the mediator has an implicit ethical and moral responsibility to influence a settlement that adequately serves the child's interests. There are no absolute moral or legal standards that clearly define a child's best interests in a given custody case. Although joint custody appears to be fair to all the parties, it may not be in the best interest of the child given the particular lifestyles and personalities of the parents and the child's need for a stable and consistent environment. Fairness in a custody agreement is not only related to the individual personalities involved, but also to the ongoing (albeit divided) family system. Reduction of interparental strife is most fair for the child in the long run. At the sociopolitical and cultural levels, the mediator must consider the traditional roles of mothers and fathers in childrearing as well as sociopolitical forces influencing change in such roles, e.g., the feminist movement. Finally, the mediator must consider moral issues in determining fairness in the custody agreement; for example, the mediator must decide whether it is morally fair for the spouse who initiated the divorce to receive the same amount of time with and control over the children as the spouse who wanted to keep the family intact. Nine references are listed.