• ODD, conduct disorder (CD), and attention deficit hyperactivity disorder (ADHD) using a Diagnostic Interview Schedule for Children [ Time Frame: Measured at Year 1 follow-up visit ] [ Designated as safety issue: No ]
• Disruptive Behavior Disorders Rating Scale [ Time Frame: Measured at Year 1 follow-up visit ] [ Designated as safety issue: No ]

• ODD, conduct disorder (CD), and attention deficit hyperactivity disorder (ADHD) using a Diagnostic Interview Schedule for Children [ Time Frame: 1-year follow up ]
• Disruptive Behavior Disorders Rating Scale [ Time Frame: 1-year follow up ]
• Clinical Global Improvement Rating Scale: The current severity of the child's oppositional behavior, the degree to which the child's behavior has improved since the beginning of treatment, and the degree to which each parent is adhering to treatment [ Time Frame: 1-year follow up ]

• Behavior Assessment System for Children [ Time Frame: Measured at Year 1 follow-up visit ] [ Designated as safety issue: No ]
• Parent Satisfaction Questionnaire: Parental satisfaction with the treatment approach and the strategies they use to discipline their children in terms of both difficulty and usefulness [ Time Frame: Measured at Weeks 4 and 7, immediately post-treatment, and Year 1 follow-up visit ] [ Designated as safety issue: No ]

• Behavior Assessment System for Children [ Time Frame: 1-year follow up ]
• Parent Satisfaction Questionnaire: Parental satisfaction with the treatment approach and the strategies they use to discipline their children in terms of both difficulty and usefulness [ Time Frame: Weeks 4 and 7, immediately post-treatment, and 1-year follow up ]

This study will evaluate the effectiveness of two different psychosocial therapies, parent management training and collaborative problem solving, in treating children with oppositional-defiant disorder.

Oppositional-defiant disorder (ODD) is characterized by a recurrent pattern of developmentally inappropriate levels of negative, defiant, disobedient, and hostile behavior toward authority figures. Behaviors associated with ODD include temper tantrums; persistent stubbornness; resistance to directions; unwillingness to compromise, give in, or negotiate; deliberate or persistent testing of limits; and verbal and minor physical aggression. The usual treatment approach for children with ODD is parent management training (PMT). PMT primarily involves teaching parents strategies to respond consistently and correctly to their child's behavior. However, PMT does not always lead to longstanding results and there is a need for alternative treatments. Collaborative problem-solving (CPS) is a treatment approach that involves both the parent and child by teaching parents to help their child control their emotions and to problem-solve as a family. This study will compare the effectiveness of CPS and PMT in treating children with ODD.

Participants in this open-label study will include children with ODD and their parents. Participants will be randomly assigned to one of three groups: CPS, PMT, or waitlist control. Parents assigned to the CPS group will be taught strategies to help their child identify and regulate emotions and to solve behavior problems together as a family. Parents assigned to the PMT group will be taught how to respond consistently and appropriately to their child's positive and negative behaviors. Participants assigned to the waitlist control condition group will wait 10 weeks before treatment begins. Participants will attend a 1-hour treatment session each week for 10 weeks. In order to determine whether treatment is effective, participants will be asked to complete a variety of questionnaires, talk with their child about solving problems, and complete a structure diagnostic interview prior to the beginning of treatment, following treatment, and at a 1-year follow-up session. Parents will be asked to submit their child's school grades and school attendance records. If granted permission by the parents, the child's teacher will complete a questionnaire regarding the child's behavior in school for the year prior to participating in the study and up to 1 year after treatment. The information collected will help to determine how treatment affects each child's progress.

• Behavioral: Parent management training (PMT)
• Behavioral: Collaborative problem solving (CPS)
• Behavioral: Waitlist control

• Experimental: Participants will receive collaborative problem solving.
• Active Comparator: Participants will receive parent management training.
• Active Comparator: Participants assigned to waitlist control will receive one of the two treatments after a 10-weeks waitlist period.

Inclusion Criteria for Children:

• Meets DSM-IV criteria for oppositional-defiant disorder
• Parent or guardian willing to provide informed consent

Exclusion Criteria for Children:

• History or current diagnosis of CD, autism, pervasive developmental disorders (PDD), or any psychotic disorder
• An estimated Full Scale IQ below 80
• Current suicidal or homicidal ideation