Climate change, driven by human activities, is one of the greatest challenges facing humanity today. Our excessive consumption and reliance on fossil fuels have brought us to a critical tipping point that demands immediate action towards more sustainable practices prioritising the climate crisis and social equity. This special issue aims to explore how design can contribute to accelerating transitions towards sustainable futures. It focuses on developing more sustainable solutions and practices and on how these can displace unsustainable incumbent solutions. This raises new questions regarding co-design methods in social sustainability, which may affect the adoption and accessibility of sustainable solutions, ensuring they are equitable and just. Moreover, it explores how design collaborations can be structured within open-sustainable design networks and how design can be strategically directed to promote paths for innovation towards desired sustainable futures.