The German electricity sector has been undergoing profound regulatory interventions by lawmakers since the end of the last decade: its monopoly position has been abolished, allowing customers for the first time to freely choose both their provider and a tariff. While customers expressed a very high willingness to switch during the initial phase of liberalization, the actual provider changes were relatively few. Currently, however, the continuously rising electricity prices from established providers are fueling the willingness of German electricity customers to switch. Although customers also have the option to choose an environmentally friendly tariff, the market share for green electricity is currently still considered (yet) low. Against this backdrop, energy supply companies (EVU) are left wondering what reasons are decisive for customers.