Caregiver rating scales represent an important component of comprehensive child neuropsychological assessments for conditions such as Attention-deficit/Hyperactivity Disorder (ADHD); however, low inter-rater reliability (parent vs. teacher) often complicates interpretation. It has been challenging to identify the factors contributing to inter-rater variability, particularly when parents and teachers complete slightly different versions of the same rating scale. The present study examined the associations between parent- and teacher-reported executive functions in 84 children, ages 4-5 years, with and without symptoms of ADHD, using the Behavior Rating Inventory of Executive Function-Preschool (BRIEF-P). Use of the BRIEF-P allows for direct comparison of symptom ratings because parents and teachers complete the exact same measure. Significant associations between raters were observed on 4 of 5 BRIEF-P subscales when rating children with ADHD, but on only 1 subscale when rating typically developing (TD) children. The Shift scale in particular displayed low, nonsignificant inter-rater association in both groups. Significant group-by-rater interactions were observed for Working Memory and Plan/Organize scales, and driven by larger inter-rater T-score discrepancies in the TD group, such that teachers rated children as having more symptoms than parents. Conversely, examination of raw scores reflected no significant rater differences in the TD group, but significant or nearly significant differences on multiple scales in the ADHD group, such that parents rated more symptoms than teachers. Inter-rater associations for the BRIEF-P appear to vary based on who is being rated (i.e., children with or without ADHD), the specific subscales, and whether standardized or raw scores are analyzed. (author abstract)