This book is a timely review of recent advances on the construction and functions of organic thin films by a variety of techniques. The component molecules are relatively simple ones with self-organizing properties, i.e., ordered molecular assembly characteristics. The contents are arranged from the fundamental concepts of molecular assembly of self-organizing molecules to the potential biological applications of protein assemblies, supramolecular species.<P>Recently, many promising applications for new electric, magnetic or optical devices, biomimetic membranes etc. have been the subject of investigation. However, fundamental studies on molecular assembly characteristics and functions for mono-, bi- and multi-layers, Langmuir-Blodgett films are indispensable to future technological innovations for molecular electronic devices and biological sensors.