This paper describes the background of microelectronics science and technology that influenced the development of molecular electronics (ME) and includes a description of some thoughts on the development of molecular circuit elements. Three basic principles are proposed and exemplified by a particular example of a suitable molecule. It is pointed out that as the size of electronic devices approaches molecular dimensions, ME promises to have distinct advantages over other technologies because the component function can be an outcome of the electronic structure of the molecule. A plan that can lead to the development of the ME concept with the scientific and technological knowledge of the present day is proposed. Copyright © 1992 John Wiley & Sons, Inc.