Regulating the use and engineering of nanomaterials is problematic owing to scientific uncertainty and controversy over their safety. To pave the way for regulatory approval and to build consumer confidence, the European Commission's Joint Research Centre and the European Academies Science Advisory Council have identified factors to help assess the benefits and risks of nanomaterials to health (see go.nature.com/utmi3d).

Our analysis indicates that formulation of a coherent public policy will depend on scientists closing knowledge gaps in safety research, on gathering more data to connect science and regulation, and on training graduate students in nanotechnology research. Policies will need to be flexible to accommodate fresh discoveries in this rapidly advancing technology.

More dialogue on nanomaterials is needed among private and public research groups, regulators and the public.

Genetic modification of crops has taught us that consumer acceptance as well as regulatory approval are needed for successful implementation of new bioscience technologies. To limit alarmist media assertions about nanomaterials, scientists have a responsibility to provide accessible and accurate information for the public.