Title: Beyond Technical Delivery: Integrating Commercial Strategy into the Core of Capital Project Leadership Abstract: This article examines the critical yet historically overlooked integration of commercial strategy within the domain of project-based leadership, with a specific focus on capital-intensive and engineering-driven sectors. It argues that mainstream project management frameworks exhibit a significant blind spot by neglecting the commercial governance, contractual foresight, and profit-oriented decision-making essential for project viability. Through a synthesis of foundational literature and contemporary thought leadership, the analysis traces the evolution of commercial management as a distinct discipline operating at the interface of project execution and corporate strategy. The paper positions this integration not as a peripheral support function but as a central competency for engineering managers and project leaders, enabling them to navigate external partnerships, manage contractual ecosystems, and ensure that technical delivery aligns with business profitability and client value creation. We conclude by advocating for a paradigm shift in professional education and practice, where commercial acumen is embedded within the core competencies of technical project leadership to enhance organizational resilience, strategic alignment, and sustainable success in complex project environments.