Title: Mapping the Managerial Mindset: Theoretical Underpinnings of Commercial and Contractual Competence in Project-Based Enterprises Abstract: This study investigates the foundational knowledge base essential for professionals operating at the nexus of project execution and commercial strategy in capital-intensive sectors. Through a global survey of practitioners affiliated with a leading contract and commercial management association, this research maps the familiarity and perceived relevance of 97 theoretical constructs drawn from management science, economics, law, and organizational studies. Findings identify a core set of highly relevant theories, including negotiation analysis, value-driven decision-making, risk intelligence, contractual governance, and strategic leadership. Cluster analysis reveals coherent knowledge groupings, while statistical comparisons highlight significant divergence in theoretical awareness based on professional function (e.g., procurement vs. sales support) rather than geographical region or academic background. The study contributes to the professionalization of commercial project leadership by delineating a multidisciplinary body of knowledge that integrates technical project delivery with business acumen, financial stewardship, and legal foresight. Results underscore the importance of integrative learning frameworks in engineering management education and the development of hybrid professionals capable of navigating the contractual, financial, and relational complexities of modern project enterprises.