Michael Lettenmeier workd as a researcher, consultant and trainer in the fields of sustainable consumption and production, sustainable resource use and footprint calculation. During the recent years, he has set a special focus on sustainable lifestyles and developed the 8 tonnes resource cap for sustainable lifestyles. He is consulting and training the implications of the 8 tonnes concept for households, business, design and different organizations. He is working with his own company, D-mat ltd., and as a member of the research group Sustainable Production and Consumption at Wuppertal Institute. Michael is finalizing his doctoral dissertation on one-planet lifestyles and the role of households and design in achieving them at the NODUS Research Group on Sustainable Design at Aalto University in Helsinki.