Paternity covers all the matters related to proving the parentage of a child or children. For married couples, paternity of a child is assumed to be the spouse, unless there is a court order or judgment stating otherwise. For unwed parents, paternity can be established by signing an Affidavit of Parentage or by filing a paternity action with the court.

Legally establishing paternity or determining that someone is not the parent of child can have a significant impact on divorce settlements, property division, child custody, child support and the ability to move out of state with the children. Determinations of paternity can also have a significant impact on interstate conflict between unwed parents.