NEMS or nanoelectromechanical systems are similar to MEMS but smaller. They hold promise to revolutionize abilities to measure small displacements and forces at a molecular scale, and are related to nanotechnology.

There are two approaches most researchers accept as standard paths to NEMS. The top-down approach can be summarized as “a set of tools designed to build a smaller set of tools”. For example, a millimeter sized factory that builds micrometer sized factories which in turn can build nanometer sized devices. The other approach is the bottom-up approach, and can be thought of as putting together single atoms or molecules until a desired level of complexity and functionality has been achieved in a device. Such an approach may utilize self-assembly or mimic molecular biology systems.