This paper compares the sensitivity and specificity of a five-item Rapid Alcohol Problems Screen (RAPS) optimized in this sample with the CAGE, brief MAST, AUDIT, TWEAK, History of Trauma Scale and breathalyzer reading against ICD-10 criteria for alcohol dependence or harmful drinking, by gender, ethnicity and injury status in a probability sample of emergency room patients (n = 1330) from the University of Mississippi Medical Center. The RAPS performed better than all other screening instruments for the total sample of current drinkers who reported ever having had three or more drinks at one time (sensitivity of 90%, specificity of 78%), and performed consistently better across all subgroups than any other single instrument, even at alternate cut points. The Rapid Alcohol Problems Screen may hold promise for use in clinical settings in identifying those who could benefit from a brief intervention or referral for problem drinking, particularly since the instrument is short and patients need not be asked additional questions after screening positive on one of the five items. Further research is necessary to analyze and compare the performance of the RAPS with other screening instruments across demographic subgroups in other emergency room and primary care settings.