This research analyses how different business actors can contribute to sustainability transitions. It draws on the case of the ongoing transition towards higher levels of animal welfare in the German egg industry. For this industry the share of organic sales is higher than for any other German industry. The analysis uses the theoretical framework of the multi-level perspective and draws on documentary information, interviews and direct observation. The results reveal that sustainable entrepreneurs at the niche level support the transition of the German egg industry by continuously creating transformative innovations, but do not aim at changing the mass market. Incumbent corporations have been fast in reacting to these changes and adopted selected niche level innovations in a way which stabilised the regime. The paper finds that relatively comprehensive changes are possible via reconfigurational pathways of transitions.