The purpose of this study was to develop the Complex Trauma Screener (CTS), a brief screener (seven items) of the ICD-11 trauma disorders that can be used in “quick-paced” facilities. We examined the factor structure of the CTS in two separate samples: civilian college students (N = 823) and military veterans (N = 130) who reported exposure to at least one traumatic event. Confirmatory factor analyses (CFAs) supported two highly-correlated factors (post-traumatic stress disorder [PTSD] and Disturbances in Self-Organization [DSO]) that loaded on the ICD-11-consistent items. The model fit indices indicated good to excellent model fit in both samples, and the internal consistencies for the scales were borderline to good (α = 0.68-0.86). Supplementary analyses supported the gender invariance of the CFA model in the civilian student sample, as well as convergent (with another trauma inventory) and discriminant validity (with borderline disorder features, depression, and mania) of the CTS in both samples. The CTS is, to our knowledge, the shortest instrument designed to measure the ICD-11 trauma disorders and is ideal for “fast-paced” facilities that have significant assessment time restraints. The CTS is, therefore, is a psychometrically-validated instrument that can help mental health professionals efficiently screen adults for ICD-11 trauma disorders.Copyright © 2024. Published by Elsevier B.V.