This special issue of ITCON brought together ten papers on Construction 4.0 related topics. These papers are drawn from papers presented at the 20th International Conference on Construction Applications of Virtual Reality (CONVR 2021) held at Teesside University, Middlesbrough TS1 3JN, the UK, in October 2020. CONVR is one of the world-leading conferences in the areas of Virtual Reality, augmented reality and building information modelling. Each year, more than 100 participants from all around the globe meet to discuss and exchange the latest developments and applications of virtual technologies in the architectural, engineering, construction and operation industry (AECO). The conference is also known for having a unique blend of participants from both academia and industry. The overarching theme for CONVR2020 was "Enabling the development and implementation of Digital Twins."