Nanotechnology has the potential to develop new materials and devices, with applications covering a wide range of fields from medicine to textiles. However, concerns have been raised about the potential impact on health and the environment. The Health Protection Agency has responded to the challenge of the public health concerns associated with nanomaterials by establishing the National Nanotoxicology Research Centre (NNRC), a principal part of which is an inhalation facility.  Aerosol science has played a key role in the development of the facility, in the design and installation of a system for the production of stable and reproducible nanoparticle aerosols and their characterisation and delivery. Aerosol science will play a key role in tackling many of the challenges which lie ahead in the field of nanotoxicology, for example in the development of methods to characterise high aspect ratio nanofibres and in understanding their transport dynamics through the respiratory tract.