The inspiration for lipid bilayer research, without question, comes from the biological world. Although self-assembled bilayer lipid membranes (BLMs) in vitro, were first reported in 1961, experimental scientists have been dealing with BLM-type interfacial adsorption phenomena since Robert Hooke's time (1672). BLMs (of planar lipid bilayers) have been used in a number of applications ranging from basic membrane biophysics including transport. practical AIDS research, and 'microchips' studies, to the conversion of solar energy via water photolysis, to biosensor development using supported bilayer lipid membranes (s-BLMs), and to photobiology comprising apoptosis and photodynamic therapy. This paper presents an overview of the origin of the lipid bilayer concept and its experimental realization, as well as the studies of our laboratory and recent research of others on the use of BLMs as models of certain biomembranes. In addition, we describe briefly our present work on supported BLMs as biosensors and molecular devices; the experiments carried out in close collaboration with colleagues on s-BLMs are delineated.