A screening instrument used to identify young children at risk for behavioral and emotional difficulties, the Behavioral and Emotional Screening System Teacher Rating Scale-Preschool was examined. The Rasch Rating Scale Method was used to provide additional information about psychometric properties of items, respondents, and the response scale. Using a representative U.S. sample of 1,485 children, the structure of the screener, performance of the rating scale, and coverage of the Maladaptive Behavior construct were investigated to identify children with emerging behavioral and emotional difficulties. Items measuring Internalizing and Externalizing Problems indicated greater efficiency for assessing at-risk behavioral and emotional problems, whereas items measuring emerging school problems or adaptive skills contributed little to the assessment of risk. Differential item functioning was examined for by age and found to be present for roughly one third of the items. Implications for scale development, screening young children, and use of screening information are discussed. (author abstract)