Objectives: To determine the reliability and validity of the Saliba Postural Classification System (SPCS). Methods: Two physical therapists classified pictures of 100 volunteer participants standing in their habitual posture for inter and intra-tester reliability. For validity, 54 participants stood on a force plate in a habitual and a corrected posture, while a vertical force was applied through the shoulders until the clinician felt a postural give. Data were extracted at the time the give was felt and at a time in the corrected posture that matched the peak vertical ground reaction force (VGRF) in the habitual posture. Results: Inter-tester reliability demonstrated 75% agreement with a Kappa��=��0.64 (95% CI��=��0.524���0.756, SE��=��0.059). Intra-tester reliability demonstrated 87% agreement with a Kappa��=��0.8, (95% CI��=��0.702���0.898, SE��=��0.05) and 80% agreement with a Kappa��=��0.706, (95% CI��=��0.594���0818, SE��=��0.057). The examiner applied a significantly higher (p��<��0.001) peak vertical force in the corrected posture prior to a postural give when compared to the habitual posture. Within the corrected posture, the %VGRF was higher when the test was ongoing vs. when a postural give was felt (p��<��0.001). The %VGRF was not different between the two postures when comparing the peaks (p��=��0.214). Discussion: The SPCS has substantial agreement for inter- and intra-tester reliability and is largely a valid postural classification system as determined by the larger vertical forces in the corrected postures. Further studies on the correlation between the SPCS and diagnostic classifications are indicated.