This two-volume set IFIP AICT 701-702 constitutes the refereed post-conference proceedings of the 20th IFIP WG 5.1 International Conference on Product Lifecycle Management: Leveraging Digital Twins, Circular Economy, and Knowledge Management for Sustainable Innovation, PLM 2023, held in Montreal, QC, Canada, during July 9-12, 2023.The 61 regular papers included in this book were carefully reviewed and selected from 116 submissions.They are organized in the following thematic sections:Part I: Technology implementation: augmented reality, CPS and digital twin; organisation: knowledge management, change management, frameworks for project and service development; modelisation : CAD and collaboration, model-based system engineering and building information modeling.Part II: Circular economy: characterization, criteria and implementation; interoperability technology: blockchain, Io T and ontologies for data exchange; learning and training: from AI to a human-centric approach; smart processes: prediction, optimization and digital thread.