In recent years, great focus has been placed upon polymer thin films. These polymer thin films are significant in many technological applications, ranging from coatings and adhesives to organic electronic devices, as well as sensors and detectors. Electropolymerization is the polymerization in the presence of an electrical current. Polymerization is any process in which relatively small molecules, called monomers, combine chemically to produce a very large chainlike or network molecule, called a polymer. The monomer molecules may be all alike, or they may represent two, three, or more different compounds. Usually at least 100 monomer molecules must be combined to make a product that has certain unique physical properties -- such as elasticity, high tensile strength, or the ability to form fibres -- that differentiate polymers from substances composed of smaller and simpler molecules; often, many thousands of monomer units are incorporated in a single molecule of a polymer. Electrochemical polymerisation is preferable, especially if the polymeric product is intended for use as polymer thin films, because electrogeneration allows fine control over the film thickness, an important parameter for fabrication of devices. Moreover, it was demonstrated that it is possible to modify the material properties by parameter control of the electrodeposition process. This book deals with introductory topics and fundamentals as well as advanced insights. The book provides a timely overview of a recent state of knowledge regarding the use of electropolymerization for new materials preparation, as well as conducting polymers and several potentials of applications.