This note provides an overview of good practice standards in Social Impact Assessment (SIA). It has been prepared by the Inter-American Development Bank (IDB), to provide guidance to practitioners and decision-makers. By applying the approach presented in this note, it is expected that the quality, consistency, and operational relevance of SIAs will improve. SIA facilitates the systematic integration of social issues in the planning and implementation of projects. It improves the quality and sustainability of projects, supports and strengthens national requirements, and enhances project acceptance and local ownership. The SIA helps to identify and manage potential adverse social impacts a project may cause or contribute to, and to maximize benefits to local communities and other groups.