Abstract
The 2003 version of Principles and Guidelines for Social Impact Assessment (SIA) in the USA provides guidance for the conduct of SIA within the context of the US National Environmental Policy Act of 1970. Guidelines are integrated within six principles focusing on: understanding of local and regional settings; dealing with the key elements of the human environment; using appropriate methods and assumptions; providing quality information for decision making; ensuring that environmental justice issues are addressed; and establishing mechanisms for evaluation/monitoring and mitigation. A social impact assessment model is outlined followed by suggested social impact assessment variables. The document concludes with the detailed steps in the SIA process.