Parent ratings of their children’s behavioral and emotional difficulties are commonly collected via the Strength and Difficulties Questionnaire (SDQ). For the first time, this study addressed the issue of interparent agreement using a measurement invariance approach. Data from 695 English couples (mothers and fathers) who had rated the behavior of their 4.25-year-old child were used. Given the inconsistency of previous results about the SDQ factor structure, alternative measurement models were tested. A five-factor Exploratory Structural Equation Model allowing for nonzero cross-loadings fitted data best. Subsequent invariance analyses revealed that the SDQ factor structure is adequately invariant across parents, with interrater correlations ranging from .67 to .78. Fathers reported significantly higher levels of child conduct problems, hyperactivity, and emotional symptoms, and lower levels of prosocial behavior. This suggests that mothers and fathers each provide unique information across a range of their child’s behavioral and emotional problems.