Health care professionals dealing with teenage parents should be aware of the rights and responsibilities of teenage parents to their children. This article discusses the constitutional rights of unwed fathers, including adolescent fathers, the process of paternity determination including the right to counsel, the role of the guardian ad litem, the use of laboratory testing to establish paternity, and the statute of limitations for paternity actions. The federal program for child support enforcement and the financial obligations of the adolescent father are described. The legal rights of the father in custody disputes are outlined. The importance of health professionals being involved with the paternity adjudication process and being well informed of the legal rights and responsibilities of teenage parents have not received sufficient emphasis in the past.