So far, the discussion about boosting energy efficiency mainly focuses on individual buildings. Yet, energy efficiency concepts go beyond building insulation, the installation of a new heating system etc. The programme "Energieeffizienz in Quartier - Clever versorgen.umbauen.aktivieren" (Energy efficiency on district level - intelligent supply.modify.activate) broadens the perspective and analyses districts from an integrated and systemic perspective. The transdisciplinary programme, lead by TU Dortmund in cooperation with Ruhr University Bochum, University Duisburg-Essen, Bochum University of Applied Sciences, Wirtschaftsförderung metropoleruhr (wmr) and the Wuppertal Institute explores interdependencies, which contribute to a rise of energy efficiency and develops recommendations for the Ruhr area and beyond, until 2018. Up to 14 PhD candidates will analyse different dimensions of a district broadly ranging from structural, spatial, socio-demographic to technical, cultural and legal frameworks that currently prevent energy efficiency improvements. For the Wuppertal Institute Steven März writes his thesis about the specific conditions of shrinking districts and analyses how energy efficiency can be embedded in strategic district developments to maintain and stabilise shrinking districts.