This research aims to rectify a paucity in current research and investigates the coevolution of traditional and sustainable business models under one corporate roof. Through a paradox lens, firms’ solutions and mechanisms to cope with the paradoxical situations that arise throughout the coevolution are determined and analyzed. This is executed conducting seven case studies of Western-European firms, consulting firms, and governmentally owned consulting institutions. Results show the array of responses firms deploy to address paradoxical areas of competing demands of economic, social, and environmental foci, organizational culture and mindset, training and staffing, resource allocation, and the stakeholder environment during the coevolution of traditional and sustainable business models, and four different coping strategies are derived from the data.