ABSTRACT: While public attention has been focused on Escherichia coli outbreaks, genetic engineering, and mad cow disease, nanotechnology has quietly taken its place at the forefront of scientific innovation and is poised to revolutionize numerous industries and fields of study. Although nanotechnology has been on the radar of researchers and developers for decades, it is only in the past few years that real-world applications have become a pervasive reality. Some of the most promising applications are in the areas of consumer products regulated by the U.S. Food and Drug Administration (FDA), including new and over-the-counter drugs, medical devices, cosmetics, and food and food packaging. Despite the incredible social and economic potential of nanotechnology, FDA faces numerous hurdles in the regulation of these products. This article explores the current state of our scientific understanding of nanotechnology, human and environmental health and safety concerns, the strengths and weaknesses of FDA's existing regulatory authority, and current efforts to address these and other issues relating to the development, understanding, and promotion of nanotechnology. In addition, the article proposes various regulatory and policy considerations FDA should take into account in addressing nano-based concerns.