THIS PAPER introduces a new field called Physics of Maintainability. This is a concept for an organized scientific approach to the solution of special design oriented problems in maintenance. The conventional maintenance approaches can be strengthened and provided with adequate tools and techniques for the new challenges being raised by the recent advances in the electronic state-of-the art. This paper describes the new field and discusses some familiar aspects of maintenance which will be affected by it. Materials in Design, Aid to Trouble Isolation, Applications to Microelectronics and Implications of Maintenance in Space are some of the topics discussed.