We report on the structural principles and requirements for the controlled formation of supramolecular architectures of electron transfer protein layers at electrode surfaces functionalized by organic mediator layers, organized by self-assembly or Langmuir/Blodgett/Kuhn technique. STM and AFM are employed to elucidate at the molecular level details of the monolayer formation, in particular, at early stages of the nucleation and growth process of SAMs. Optical methods, in particular surface plasmon spectroscopy and mica waveguide spectroscopy are used to observe on-line the build-up of these multilayer assemblies. With a combined surface plasmon spectroscopy and cyclovoltammetry set-up it is possible to investigate the interfacial architecture and the electron transfer reactions of the proteins simultaneously.