Background: Although parental concordance for any psychiatric disorder is known to be associated with elevated risk for offspring disorder, little evidence is currently available from prospective longitudinal studies regarding the association of parental concordance with offspring risk for anxiety, conduct, depressive, and substance use disorders. Sampling and Methods: Psychiatric interviews were conducted with 593 mothers and their biological offspring at mean offspring ages 14, 16, 22, and 33. Results: Offspring risk for ≧1 psychiatric disorder was significantly greater if both parents had a lifetime history of psychiatric disorder than if only one parent had a lifetime history of disorder. Parental concordance for generalized anxiety disorder (GAD) was associated with a significant increase in offspring risk for anxiety disorders, above and beyond the risk attributable to having one affected parent. In addition, parental concordance for GAD was associated with elevated risk for offspring depressive disorders, and parental concordance for substance use disorders was associated with elevated offspring risk for conduct disorder. Conclusions: Parental concordance for GAD may be associated with elevated risk for offspring anxiety disorder, above and beyond the risk associated with having one affected parent.