The benefit is much greater when both parents enroll.
Children who have two parents can get mixed up by inconsistent or conflicting approaches. Parents who take P.E.T. together can help each other practice the new skills.
The new skills and methods are much easier to apply by parents when their children are very young.
Such parents don't have to unlearn a lot of old habits. What's more, younger children have not yet developed stubborn coping mechanisms and resistances to their parents' ineffective methods. Furthermore, parents of young children will have more time to become skillful in the new methods before problems get serious.
Parents of adolescents find the skills and methods of P.E.T. particularly valuable.
They lessen the usual storm and stress as parents and teenagers come into conflict over really critical problems such as dating, drinking, dress, drugs, and almost everything else.*
*Writings from Dr. Thomas Gordon's P.E.T. pamphlet