The accelerating deterioration of global building stock, driven by aging infrastructure, environmental exposure, evolving functional demands, and heightened safety expectations, has compelled the construction industry to reassess conventional approaches to structural strengthening, repair, and rehabilitation. Within this context, fibre-reinforced polymer (FRP) composites have emerged as a transformative class of materials capable of redefining both the philosophy and practice of construction retrofitting. This research article develops an extensive, theory-driven, and critically grounded examination of FRP applications in construction projects, with particular emphasis on rehabilitation and retrofitting of reinforced concrete and masonry structures. Drawing strictly and comprehensively on the provided scholarly references, the study synthesizes decades of conceptual development, experimental validation, and applied engineering practice to articulate a holistic understanding of FRP as not merely a material innovation, but as a systemic shift in construction methodology. The article situates FRP technologies within broader discourses on sustainability, resilience, lifecycle performance, and infrastructure governance, while interrogating competing scholarly viewpoints regarding durability, failure mechanisms, constructability, and long-term performance uncertainty. Special analytical attention is devoted to the integration of FRP systems within existing regulatory, auditing, and rehabilitation frameworks, highlighting the tensions between rapid technological advancement and comparatively conservative design codes. By employing a descriptive and interpretive methodology rooted in literature-based analysis, this study elucidates how FRP interventions alter structural behavior, redistribute stresses, and extend service life under diverse loading and environmental conditions. The findings underscore that FRP retrofitting effectiveness is contingent not solely on material properties, but on design philosophy, workmanship, structural diagnosis accuracy, and contextual compatibility with existing substrates. The discussion advances a nuanced critique of current knowledge gaps, particularly regarding long-term durability, fire resistance, and socio-economic adoption barriers, while proposing theoretically grounded directions for future research. Ultimately, this article argues that FRP-based rehabilitation represents a paradigmatic evolution in construction engineering—one that demands integrative thinking across materials science, structural mechanics, sustainability studies, and policy development to fully realize its transformative potential (Bandela, 2025).