Many business activities and procedures influence the environment. This environmental impact has to be assessed. We consider companies where the procedure of measuring environmental performance is applied through an environmental management system. The benchmark methodology has been developed precisely for these companies. This benchmark methodology can be used in the initial assessment as a screening method in sectors of different economic activities. The paper surveys the methodology that is designated for the environmental performance assessment of companies in the food-processing sector and introduces the architecture of the Web environmental benchmarking and reporting system that has been also developed.