Humanity is facing unprecedented environmental, social, and economic challenges. We ask what the role of the global science community should be in tackling these challenges. Increased awareness of the social context in which science is being produced; acceptance of the importance of controversy; and reflection around normative assumptions underlying research are needed. To help solve humanity’s grand challenges scientists need to move towards a transdisciplinary view of science where knowledge emerges from a collaborative environment and where young scientists are trained to work across disciplinary boundaries and engage with policy communities.