Odour pollution is one of the most socially disruptive and technically challenging environmental hazards associated with contaminated land remediation. Unlike toxicological risks that may remain latent, malodorous emissions generate immediate community response, regulatory scrutiny, and operational constraints. Managing odour at remediation sites therefore demands a systemic, multi-layered approach to risk mitigation. This chapter examines the Swiss Cheese Model (Reason, 1990) as a framework for understanding how odour pollution events arise during soil and groundwater remediation, and how it can guide the design of robust, redundant defence architectures. Framework The Swiss Cheese Model, developed by James Reason within organisational accident theory , argues that hazardous outcomes rarely result from a single failure. Instead, they occur when latent conditions and active failures align across multiple defensive layers. Each layer is like a slice of Swiss cheese, containing weakn...