In relation to Environmental Assessments conducted in Ontario, this report aims to explain the proper function of evaluation methods, the different kinds of methods available and their characteristics, and the common pitfalls to watch for and avoid in applying these methods. This explanation is intended to be of use not only to government reviewers of submitted Environmental Assessments but also to the proponents responsible for the evaluation of alternatives in planning their projects. In this way the report, it is hoped, will make a contribution to better planning and documentation, fewer unnecessary disputes with interested parties, and greater consistency and effectiveness in review.