This article outlines the development of a 10-item measure of workplace ostracism. Using 6 samples (including multisource and multiwave data), the authors developed a reliable scale with a unidimensional factor structure that replicated across 4 separate samples. The scale possessed both convergent and discriminant validity, and criterion-related validity was demonstrated through the scale's relation with basic needs, well-being, job attitudes, job performance, and withdrawal. Overall, the present study suggests that the Workplace Ostracism Scale is a reliable and valid measure and that the workplace ostracism construct has important implications for both individuals and organizations.