The growing demand to instrument carbon-cutting strategies, improve resource efficiency, and parade compliance with UK sustainability policies has heightened the call for new digitally-enabled strategies in the construction sector. Despite the increase in awareness, a considerable share of UK construction companies remains limited in digital integration, appropriate sustainability-oriented leadership, and insufficient innovation and agility strategies, which inhibit the implementation of sustainable projects. This study examines the impact of Digital Integration and Sustainability-Oriented Leadership on Sustainable Project Delivery Performance in UK construction management, using a Sequential Mediating Model (SEM) of Eco-Innovation and Organizational Agility, with Stakeholder Pressure as a moderating factor. The survey information has been collected from 500 professionals, including project managers, sustainability officers, and digital transformation leads working in UK construction companies. Measurement and structural models were tested using SmartPLS 4.0 to assess their reliability and validity, as well as path coefficients and indirect effects. The results show that Digital Integration and Sustainability-Oriented Leadership are both significant in promoting sustainable project delivery, which occurs in a sequential manner: the antecedents trigger Eco-Innovation, thereby strengthening Organizational Agility, and eventually leading to better project delivery. In addition, Stakeholder Pressure was identified as increasing the influence of Digital Integration and Sustainability-Oriented Leadership on Eco-Innovation, highlighting the contributions of regulatory, client, and societal expectations to sustainable innovation. The research has added to the body of knowledge in construction management and sustainability through the combination of digitalization, leadership, and dynamic capabilities into a single framework, and also, it provides practical tips to enable UK construction companies to use digital systems, sustainability-oriented leadership, and innovativeness capabilities to achieve high-performing and environmentally conscientious project results.