Organisations invest in governance, sustainability planning, knowledge management and project management office (PMO) capability, but the mechanisms linking these resources to sustainable project practices remain unclear. Using 550 complete survey responses and 5,000 bootstrap subsamples, this study compares four theory-guided PLS-SEM specifications: a directeffects baseline, two mediation models and a reverse-order model. In the baseline, knowledge management (β = .466, p < .001) and PMO capability (β = .351, p < .001) were positively associated with sustainable practices; governance and planning/training had no significant unique direct association. In the first mediation model, PMO capability transmitted the associations of governance (βind = .146) and knowledge management (βind = .191) with practices, whereas planning/training was not an independent mediator. The distal–proximal model yielded four significant specific indirect effects but less favourable discrepancy statistics. The reverse ordering was comparatively weak. Knowledge management and PMO capability consistently appeared as proximal organisational mechanisms. High construct overlap, collinearity and the cross-sectional design limit causal and model-superiority claims. The findings emphasise the roles of organisational learning and PMO implementation capability in sustainability practice.

Ahmad M. S. Ahmad Shtayya, Zunirah Mohd Talib, Normalini Md Kassim, "From Organisational Foundations to Sustainable Project Practices: Comparing Rival Translation Mechanisms in PMO-Enabled Sustainability" International Journal of Scientific Research and Engineering Development, V9(5): Page(2081-2091) September - October 2026. ISSN: 2581-7175. www.ijsred.com. Published by Scientific and Academic Research Publishing.