No matter which way you look at it, nanotechnology is poised to influence our lives to some degree over the coming years. Rapid advances in our ability to engineer materials, structures, and devices at atomic and near-atomic scales are broadening our horizons at an ever-increasing rate. Nanotechnology is fundamentally based on exploiting the unique properties of nanoscale structures. However, these same properties present tough new challenges to understanding, predicting, and managing how the technology will impact health and the environment. In recent months, the need to address the potential risks associated with nanotechnology has received widespread media coverage. In April 2003, the Canadian-based nongovernmental organization Action Group on Erosion, Technology, and Concentration (ETC) made the case for a global moratorium on nanotech research until the risks are more fully understood. More recently, the UK's Royal Society and Royal Academy of Engineering stressed the need to address gaps in our understanding of the impact on health and the environment. Although the health and environmental risks of nanotechnology must be evaluated over the lifetime of products, the first point of impact in many cases will be in the workplace. So what risks are there at work? As nanotechnology is essentially a process rather than a product, this cannot easily be answered. However, the production and use of insoluble nanostructured materials has driven much of the current concern over potential health risks.