SFI External Professor Sander van der Leeuw and colleagues have released a study stating that identifying and quantifying planetary boundaries that must not be transgressed could help prevent human activities from causing unacceptable environmental change. Van der Leeuw and colleagues found that three of the Earth-system processes have already transgressed their boundaries. These include: climate change, rate of biodiversity loss and interference with the nitrogen cycle. The evidence suggests that as long as the thresholds are not crossed, humanity has the freedom to pursue long-term social and economic development.