Model Validation and Uncertainty Quantification, Volume 3: Proceedings of the 40th IMAC, A Conference and Exposition on Structural Dynamics, 2022, the third volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Model Validation and Uncertainty Quantification, including papers on:Uncertainty Quantification and Propagation in Structural DynamicsBayesian Analysis for Real-Time Monitoring and MaintenanceUncertainty in Early Stage DesignQuantification of Model-Form UncertaintiesFusion of Test and AnalysisMVUQ in Action