The aim of this paper is to present a way to measure and display the user satisfaction related to the indoor environment of a building and the environmental impact related to the energy use of the building in the same diagram, the building's environmental efficiency. Further, the aim is to evaluate the power of this concept as an overarching goal for environmental management of buildings by presenting and analysing the environmental efficiency for a number of existing buildings. The environmental impact of energy use and the quality of the indoor environment are two of the most important environmental issues related to buildings. To some extent they are related since for example less energy use for heating, which normally means less environmental impact, may cause inconvenience for the users. For a real estate manager it is thus crucial that a reduced environmental impact of a building is not achieved at the cost of an inferior indoor environment. Instead, these two issues need to be handled simultaneously which raises demands on evaluation methods. Such methods have been developed in a comprehensive Swedish research project on environmental assessment of buildings, called EcoEffect. Data on energy use and user perceptions related to the indoor environment was collected for a number of multifamily houses in Sweden. User perceptions were captured by a comprehensive questionnaire. LCA methodology was used to calculate the environmental impact for the energy use. In order to plot the environmental efficiency in a diagram, an aggregated index needs to be calculated for the user satisfaction and environmental impact respectively. Through the comprehensive questionnaire data along with construction data of the buildings, the validity of these indexes could be evaluated.In the paper, the environmental efficiency for all examined buildings is shown in the same diagram. This aggregated picture will describe the environmental performance of a stock of Swedish buildings. It can be concluded that the aggregated indexes that are necessary for the calculation of the environmental efficiency of a building are rough but nevertheless of a kind that is easily communicated and probably well suited for comparisons between buildings. However, more background information is necessary when working with improvement measures in the environmental management.The simple concept of environmental efficiency can be used to measure and analyse the quality of the indoor environment and external environmental impact simultaneously. It may be used as an overarching environmental objective in real estate management and for comparisons between similar buildings.