Universal screening for mental health has gained prominence in schools with the adoption of multitiered systems of support. However, there is a general lack of brief, psychometrically defensible instruments that assess emotional and behavioral risk. This study employed a multilevel, confirmatory bifactor analysis to evaluate the factor structure of a novel screening instrument—the Social, Academic, and Emotional Behavioral Risk Screener (SAEBRS; Kilgus & von der Embse, 2014)—examining the structure at the student (within) and teacher or rater (between) levels. Item response theory (IRT) analyses were then used to examine the functioning of 2 existing factors, social risk and academic risk, in addition to a newly introduced third factor, emotional risk, within a sample of 834 elementary and middle school students. Results indicated good fit of a bifactor model including the addition of the new Emotional Behavior subscale. IRT analyses suggested strong item-level discriminative properties (a > 1.0) for 17 of the 19 SAEBRS items and indicated that scale precision was greatest within the low to moderate range of each respective dimension (social, academic, and behavioral risk). Overall, the findings provide support for the use of the SAEBRS as a screener for mental health–related concerns. Implications for model interpretation and model use are discussed.