Nanotechnology is an emerging science that takes advantage of the novel properties of matter at the nanometer scale, and it carries with it promises of advances across a broad spectrum of applications, including electronics, pharmaceuticals, and industrial products. However, products utilizing nanotechnology may also present unique problems to human and environmental health, precisely because they do not behave in the body or environment in the manner expected from conventional materials. As the field of nanotechnology expands and becomes widely integrated across many applications, human exposure to nanomaterials will become more likely. The human health effects of such exposure remains largely unknown, though studies have linked nanoparticle exposure with a variety of impacts, ranging from inflammation to carcinogenicity. With the safety of nanomaterials still in question, this paper examines methods for preventing unwanted exposure through regulation, the likely biological responses that will follow exposure, and the safety considerations that must inform the initial stages of engineering new nanomaterials. The uncertainty of the risks posed by nanotechnology requires that some action be taken in the short-term to safeguard human health, while more information is developed regarding the adverse health effects that nanomaterials may display.