Ordered monolayers and multilayers of lipids, DNA, fatty acids and proteins, and processes of their interfacing with silicon, gold and other inorganic substrates, form the basis of a new emerging field, called molecular bioelectronics, at the crossing of molecular biology and submicron electronics. Numerous electronic and biotechnological applications result from the above supramolecular architectures, namely from the Langmuir-Blodgett (LB) films of proteins involved in molecular recognition, actuation and information processing, in catalytic activity and electron transfer, because of their unique structural and functional stability to long storage, experimental manipulation and temperatures up to 200 degrees C. Few key examples of molecular bioelectronics are here summarized.