This document provides an overview of basic concepts for environmental impact assessment (EIA). It defines key terms like "impacts" and "baseline situation." The EIA process begins with understanding the proposed activity and its development objective. It then involves screening the activity to determine the appropriate level of analysis. A preliminary assessment may be conducted for activities of moderate or unknown risk to identify impacts and necessary mitigation measures. For very high risk activities, a full EIA study is required, which involves more detailed analysis of alternatives and impacts. Public participation is an important part of transparent and effective EIA.