Systematic Literature Review: Background: Oppositional Defiant Disorder (ODD) is a relatively common childhood disorder that is associated with a number of adverse outcomes. It is often identifiable from a young age, with younger onset predicting more adverse outcomes. Preventative interventions have therefore been developed that aim to reduce the onset of ODD and its symptoms. A number of school-based preventative interventions have been implemented, but no review of their effectiveness has been conducted. Objectives: To conduct a systematic review of classroom based preventative interventions for oppositional defiant disorder. Method: Electronic databases in the psychological and educational fields were systematically searched for evidence of school-based preventative interventions. Results: Eight studies were identified that met the inclusion and exclusion criteria. These ranged from large universal based studies, to selected and indicated types of prevention. There were methodological flaws in a number of studies, particularly with regards to random assignment. Therefore, the conclusions drawn from these studies are tentative. Conclusions: There was some evidence for the effectiveness of school-based interventions for ODD. Further research is needed, with higher quality designs, to replicate and extend the findings to date. KEYWORDS: Oppositional Defiant Disorder; Prevention; School-based. Major Research Project: Background: Oppositional Defiant Disorder (ODD) describes a pattern of negative and disruptive behaviours in childhood that cause concurrent difficulties and are associated with later behaviour problems through to adulthood. A number of antecedents for ODD have been posited in the literature. This study explored how maternal depression, an internalising disorder, may be associated with ODD, an externalizing disorder, through its association with maternal anger. The relevance of mothers’ antisocial history was also explored. Methods: A community sample of 332 families were recruited to the Cardiff Child Development Study, a longitudinal design following families from pregnancy to age 7. Structural equation modeling was adopted to test a measurement model of maternal anger, then a series of hypotheses regarding the prediction of ODD when the children were 7 years of age were conducted. Maternal depression (past, antenatal and postnatal) and child ODD was measured using diagnostic clinical interview, and maternal anger through self- and partner-reported and experimenter-observation. Results: Perinatal depression showed no direct relationship with ODD in this demographically diverse sample, although mothers’ depression prior to pregnancy did. Maternal anger was related to ODD in families with social adversity (measured by low education, young parenthood, and unstable parental relationships). Mothers’ antisocial history was a unique predictor of ODD, above that of mothers’ prior depression. Conclusions: Mothers’ antisocial history is an important predictor of child ODD, and is also related to maternal anger. Maternal anger is related to child ODD in high adversity families. Recommendations for future research are provided. KEYWORDS: Oppositional Defiant Disorder; Maternal Depression; Maternal Antisocial History; Maternal Anger.