Nanotechnology, a unique ability to engineer new, often path-breaking, materials and devices at the sub-100 nm scale, offers great opportunities for innovation and discovery in engineering and science. At these length scales, conventional theories may no longer apply. The Department of Electrical Engineering at Princeton is a world pioneer in nanotechnology. The department's contributions and research are in two areas: (a) new nanofabrication technologies to make nanostructures that cannot be made by current technology; and (b) applications of nanostructures in electronics, optics, magnetics, biotechnology, and other fields to achieve innovative materials and devices with unprecedented new functionality and high performance. These innovations are of particular interest for integrated circuits, communications, energy, biotechnology, medical diagnosis, and other industries. Examples of previous work include the invention of nanoimprint lithography, bit-patterned media, DNA sequencing by nanochannels, nano-pillar molecular sorters, plasmonic solar cells and LEDs, subwavelength optical elements (nanophotonics), and biosensors for diseases/cancel early detection; design and fabrication of nanomaterials and nanotransistors (conventional, single electron, and quantum) with record high performances and small sizes. The work at Princeton EE has been widely used by many fields and has led to numerous start-ups, hence having profound impacts to both academia and industry.