This Opinion Article highlights how new applications of techniques such as neutron scattering are offering greater insights into the processes, mechanisms and rates controlling the behaviour and fate of nanoparticles in different environmental compartments. Such information is vital for successful predictive modelling of the environmental fate of engineered nanoparticles in the post-production stages of their lifecycles. The role of surface functionality (surface coatings) in influencing environmental pathways of nanoparticles is specifically discussed. (C) 2010 Elsevier Ltd. All rights reserved.