This book reviews the sources of the air pollutants responsible for building damage and the mechanisms involved. Studies investigating the relationships between pollution concentration (dose) and the resulting damage (response) are described and the latest research findings for dose-response functions are presented. Trends in pollutant emissions, ambient concentrations and building damage over time are described and future predictions are presented. Methodologies for assessing the extent of the potential problem in a region – the stock at risk – are presented. Procedures for estimating the economic implications are described and the consequences are discussed in detail, because economic factors are important for reaching policy and management decisions at local, national and international scales. Damage to cultural heritage buildings is an important additional effect which needs to be considered as the standards are revised and the factors which will need to be brought into the assessment are presented.