Joint physical custody demands a great deal from the former married partners. After all, it is something of a stretch to imagine that a couple whose marriage crashed can somehow rise to the heights to make cooperative parenting work. One Illinois lawyer notes that for the courts the main factor in deciding joint custody is "the ability of the parents to cooperate effectively and consistently in matters that directly affect the joint parenting of the child. My experience is that if the parents are able to cooperate effectively and consistently’ there would not have been a divorce in the first place."

Dr. Emery expresses his philosophical support for joint custody. "Children have two parents. Most children want to have a relationship with both their parents, and most divorced parents want relationships with their children. Family relationships can and do continue despite the many upheavals of divorce. The old model of divorce as a family feud, where only one parent raises and ’owns’ the children is well, the old model. Divorced parents can be parents even if they are no longer lovers." Yet Dr. Emery offers a number of caveats about joint custody.