As the demand for sustainable buildings rises, so does the urgency to address the persistent challenge of defects that compromise their environmental, economic, and social deliverables and performance. Despite their resource-efficient and occupant-friendly design, sustainable buildings are not immune to failures that increase costs, cause rework, and impact stakeholder confidence. This chapter investigates the nature, causes, and management of defects specific to sustainable buildings, revealing that even with green innovations, design and construction flaws remain prevalent across global contexts. Drawing on international data and case studies, the research examines how construction practices, material choices, and managerial strategies influence defect occurrences. A mixed-method approach was used to analyse defect patterns and propose a machine learning-based classification method to streamline repair and maintenance processes. The findings inform the development of a sustainable building pathology framework that guides industry stakeholders in diagnosing and mitigating defects proactively. This framework underscores the distinction between conventional and sustainable construction practices and emphasises the importance of quality control, skilled labour, integrated design, and long-term maintenance strategies. Ultimately, this chapter contributes to the advancement of defect-aware, sustainable construction management and offers practical insights for contractors, policymakers, educators, and developers aiming to enhance the longevity and performance of green buildings.