Nanotechnology is one of the fastest growing technological fields of the 21^st century. Nanotechnologies will impact numerous industries, including daily consumer products, health care, energy, and transportation. However, the success of the emerging nanotechnology applications will depend on dynamic development of nanomaterial toxicology, risk and exposure assessment. Little is known about the potential adverse health and ecological effects of exposure to engineered nanomaterials, the main components of many nanotechnologies. Concerns are coming from the initial toxicological studies as well as the research and epidemiological reports on ultrafine particle toxicity. This book provides a summary of the state-of-art knowledge on nanomaterials and nanoparticles – toxicological issues; risk assessment and control measures; public participation and educational/ethical issues; and lastly, institutional mechanisms and status reports from various countries. This book includes a summary of the most important gaps in knowledge, needs for research, and collaborations in the field of nanotechnology regarding safe application and development.