Researchers and clinicians have long hypothesized that there are temperamental vulnerabilities to depressive disorders. Despite the fact that individual differences in temperament should be evident in early childhood, most studies have focused on older youth and adults. We hypothesized that if early childhood temperament is a risk factor for depressive disorders, it should be associated with better established risk markers, such parental depression. Hence, we examined the associations of laboratory-assessed positive emotionality (PE), negative emotionality (NE), and behavioral inhibition (BI) with semistructured interview-based diagnoses of parental depressive disorders in a community sample of 536 3-year old children. Children with higher levels of NE and BI had higher probabilities of having a depressed parent. However, both main effects were qualified by interactions with child PE. At high and moderate (but not low) levels of child PE, greater NE and BI were associated with higher rates of parental depression. Conversely, at low (but not high and moderate) levels of child NE, low PE was associated with higher rates of parental depression. Child temperament was not associated with parental anxiety and substance use disorders. These findings indicate that laboratory-assessed temperament in young children is associated with parental depressive disorders; however, the relations are complex, and it is important to consider interactions between temperament dimensions rather than focusing exclusively on main effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)