The capabilities of future mobile communication devices will extend beyond merely transmitting and receiving voice, data, and video information. For example, first responders such as firefighters and emergency workers will wear environmentally- aware devices that will warn them of combustible and toxic gases as well as communicate that information wirelessly to the Command and Control Center. Similar sensor systems could alert warfighters of the presence of explosives or biological weapons. These systems can function either in the form of an individual stand-alone detector or part of a wireless sensor network. Novel sensors whose functionality is enhanced via nanotechnology will play a key role in realizing such systems. Such sensors are important because of their high sensitivity, low power consumption, and small size. This talk will provide an overview of some of the advances made in sensors through the use of nanotechnology, including those that make use of carbon nanotubes and nanoparticles. Their applicability in mobile sensing and wireless sensor networks for use in national security and public safety will be described. Other technical challenges associated with the development of such systems and networks will also be discussed.