This title presents the state-of-the-art in molecular engineering and new developments in the fields of materials science, membrane biophysics, interfaces, sensing, and intermolecular interactions including molecular recognition.Topics covered are: the organization (orientation and association) of molecules in ultrathin films (monolayers) at the air/water interface; long range order in these films and in assemblies of such films on solid substrates; the interactions with solutes in the aqueous phase (including tensides, enzymes and analytes); and the potential applications of ultrathin films as nanometric modules in devices.