<p>This study investigates the effectiveness of the Project Management Institute’s (PMI) standardized Body of Knowledge (PMBOK) in managing construction projects in the Caribbean Small Island Developing States (SIDS). Despite global adoption of PMI methodologies, there is growing concern over their rigidity and lack of contextual adaptability, especially in developing countries. Using a functionalist viewpoint, this study adopted a quantitative approach to surveyed 128 project professionals, including engineers, project managers, architects, and consultants, via structured, closed-ended questionnaires to assess perceptions of PMBOK’s challenges and limitations on construction projects. Responses were then collated, checked for validity and reliability, and analyzed to develop an SEM. The study's findings reveal that although PMBOK provides valuable project management tools, its universal approach fails to account for the diverse complexities, sizes, and socio-political influences of construction projects in SIDS. Participants highlighted limitations in leadership, stakeholder engagement, adaptability, and training initiatives. Major challenges identified were political interference, rigid structures, and inadequate consideration of local contexts. The SEM model validated these constraints, suggesting that the current PMBOK framework restricts project flexibility, innovation, and decision making. The study concludes that PMBOK standards need contextual adaptation to be truly effective in diverse environments. Recommendations include enhancing leadership training, tailoring project methodologies to local needs, and integrating localized risk and communication strategies. Therefore, this study offers important advice for improving project outcomes in the Caribbean and similar developing regions, emphasizing that a flexible, tailored approach is essential for successful project delivery.</p>