It considers, like its predecessor, the issues of scientific evidence as the basis for action/inaction, the multiple, often complex factors and feedback loops in play, many of which are not fully understood, as well as the interfaces between science, policy and society and how all actors can move together towards necessary actions in the context of heightened systemic risks, and substantial unknowns.

Part B - Emerging lessons from ecosystems contains the following chapters:

• Booster biocide antifoulants: is history repeating itself?
  Andrew R. G. Price and James W. Readman
• Ethinyl oestradiol in the aquatic environment
  Susan Jobling and Richard Owen
• Climate change: science and the precautionary principle
  Hartmut Grassl and Bert Metz
• Floods: lessons about early warning systems
  Zbigniew W. Kundzewicz
• Seed‑dressing systemic insecticides and honeybees
  Laura Maxim and Jeroen van der Sluijs
  See also: additional debate between Bayer CropScience and authors of this chapter

• Ecosystems and managing the dynamics of change
  Jacqueline McGlade and Sybille van den Hove