This part of the handbook series on EIA deals with methodology. "EIA methodology" means the basic elements of EIA and their functions, as well as principles for implementing them in road and rail planning. The purpose of the handbook is to contribute to improved application of EIA and clearer integration of EIA in road and rail planning and design planning. It will support a development towards EIA documents being aimed at the essential and relevant environmental issues in every project. The handbook should be used together with the report Planläggning av vägar och järnvägar version 1.0 which can be downloaded from our website.