In times of global climate change and rising scepticism towards conventional energy production, saving energy has become one of the most pressing societal goals. The task of saving energy is an interdisciplinary one: while engineers are trying to find technological innovations to reduce energy consumption, psychologists should concentrate their efforts on the behavioural side of energy consumption.In Western societies a big deal of energy consumption emerges in public buildings and private households. Here, many curtailment behaviours concerning energy use are shown. It is reasonable to believe that most of these everyday behaviours are determined by habits. Therefore, psychological interventions targeting behavioural changes towards energy saving in everyday live should focus on breaking these habits and establishing new, more energy-efficient ones.In the research project “Change”, a specific energy saving campaign has been developed to promote energy-efficient behaviour of employees in public buildings. Elements particularly to break energy consumption habits were integrated in the intervention package.In winter 2008/09 and 2009/10, the intervention was initially tested in eight universities using three different versions. Short term results were promising, especially when experts’ support was given during the intervention implementation. Long term effects were mixed and depended on the type of energy consumption. While electricity could be saved in the long run, heat energy consumption revealed rebound effects.During the presentation, the results of the interventions will be exemplified in detail. Especially, we would like to discuss possible reasons for the varying results concerning electricity and heat consumption. Beyond that, we would like to present and discuss our latest approaches to improve the intervention.