Thirty-seven (37) couples experiencing child behavior problems and concurrent marital conflict were randomly assigned to one of two variants of a group parent training program, either Standard Group Triple P (SGTP; n=19) or Enhanced Group Triple P (EGTP; n=18). SGTP incorporated 8 sessions (4 group sessions and 4 telephone consultations) and taught parents to identify the causes of child behaviour problems, promote children's development, manage misbehavior and plan ahead to prevent child behavior problems in “high risk” parenting situations. Families in the EGTP condition received SGTP plus 2 additional group sessions of parent support training that taught partners to support one another to parent as a team. These additional sessions included information and active skills training in communication skills; giving and receiving constructive feedback; holding casual conversations; supporting each other when problems occur; holding problem solving discussions; and improving relationship happiness. There were significant improvements from pre- to post-intervention for both conditions, on measures of disruptive child behavior, dysfunctional parenting style, conflict over parenting, relationship satisfaction and communication. No differences, however, were found between the two conditions, with both the EGTP and the SGTP programs resulting in similar outcomes. In the main, initial treatment effects for both mothers and fathers were maintained at 3-month follow-up.