To achieve an economy within ecological boundaries that meets the needs of all requires societal transitions (i.e. systemic changes of collective cultures, structures and practices). Such a societal and economic transition requires corporate and entrepreneurial organisations to transform their businesses, business models and societal roles. While the importance of companies for sustainable development has been acknowledged in the existing literature the link between transformations at the organizational level and sustainability transitions beyond organizational boundaries needs further investigation. This contribution therefore unpacks the duality of companies in sustainability transitions: they are subject to the transformative changes in the economy and society, and they can be leaders of sustainability transitions of the economy and society. Companies are challenged to proactively manage a simultaneous build-up of sustainable and phase-out of unsustainable products, services and practices. Key approaches for sustainability transformation management are discussed and conclusions for research and practice deducted.