MILLIONS OF SINGLE parents stand to benefit from passage of a new federal law that requires states to help in the collection of child support payments. States must now authorize automatic wage withholding of overdue child support payments, for example. They must assign state tax refunds to custodial parents in payment of this obligation. Only one family in four has been receiving the full amount of support ordered by a court, and untold numbers of custodial parents and their children have suffered. Now state agencies must implement more effective methods to help them.

Collecting child support payments, however, is a problem only for half the divorced parents. The others, the parents who do not have custody, often face another unpleasant aspect of separation -- one that is aggravated when hostility between parents continues even after a divorce. Their difficulty is enforcing court-ordered visitation rights. In the past, custodial parents often retaliated when support payments were delayed by refusing to allow a former spouse to visit the children. Some parents were excluded even when support had been faithfully paid. Neither tactic is fair. Failure to allow visitation is as much a violation of a court order as the refusal to pay support.

A few jurisdictions have begun to take steps to aid noncustodial parents who want to maintain ties to their children. Michigan is the leader nationally, and in this area Prince George's County is the first to experiment with a new mechanism to enforce visitation rights. Starting in January, the county's Office of Child Support Enforcement will employ a special investigator to act on complaints from noncustodial parents. The investigator will have no police or judicial powers but will contact custodial parents, arrange meetings and attempt to resolve conflicts without going to court. Legal action can be time-consuming and expensive to a parent, and if an investigator can, through pressure and mediation, persuade a custodial parent that the terms of the divorce decree must be observed, that is all to the good.

As one divorced father points out, visitation rights are a form of child support too, for a child's continuing loving relationship with each parent is as important to his development as the material goods that money provides. The Prince George's program, which will run at least through April, recognizes that both parents have equally important rights that deserved the support of the community. Other jurisdictions should take careful note.