Molecular mechanical and supramolecular systems have been with us for some time, but the means for their programmed control have often been lacking. In order to construct useful nanomechanical devices, the structures need not only to have a mechanical function, but this function needs to be addressable. Ideally a nanomechanical system will be 'programmed' for a particular task, that is, it will be sensitive to its environment and contain the processing ability to act appropriately without external control at every step of its operation. Here, we review the developing methods for the integration and interfacing of molecular mechanical components and the solutions that have been found for performing information functions (memory, processing) on a molecular scale. Fundamental units such as photochromic, redox, fluorescent and supramolecular moieties are introduced and their combination into multicomponent covalent or supramolecular systems is discussed. The immobilization of molecular devices on surfaces is given special attention, along with methods for the transduction and amplification of output signals from the devices.

Keywords: Molecular machines, Molecular switches, Molecular memory, Molecular computing, Supramolecular chemistry, Molecular optoelectronics, Command surfaces, Monolayers, Nanotechnology