The chapter presents the application of the Analytic Hierarchy Process (AHP) method in the field of environmental management. The work shows how to use the results of environmental engineering tools or models as an input for the AHP method. Three case studies are presented: selection of the best municipal solid waste disposal system, assessment of the tap and bottled water consumption on the environment, and selection of the heat pump for the individual home. In the first case study, the AHP analysis was required to assess the environmental impact of waste disposal system. This was done by the use of Integrated Waste Management model (IWM-1), which delivered results aggregated, at the next step, into Life Cycle Analysis (LCA) categories. The obtained results were used in the AHP analysis to choose the best scheme for the waste disposal system. In the second case study, the AHP method was used to evaluate different patterns of water drinking. Obtained results help decision makers in assessing regional and individual environmental impact if the drinking pattern changes. Selected evaluation criteria were solid waste stream, energy consumption, carbon dioxide emission, and Ecoindicator 99 H/A points. The third case study presents the method of heat pump selection. The environmental performance criteria were developed using the criteria of the ecolabeling program. All three case studies are based on real data.