This paper is a proposal for a standard for the user-system interface protocol. The standard was developed when we noticed that clerical employees in business offices were being asked to use several different computer systems (via terminal-type devices). Each of these systems was implemented for unique applications. And, although in some cases multiple units were from the same manufacturer, each had a different sign-on protocol. Our interest is mostly in security, and we noticed that the result of this welter of varying processes was almost invariably the posting of "how to sign on" instructions, including passwords. Hence, the ALACS proposal.The proposal has been given to IEEE for consideration, and to the National Bureau of Standards, who are working on similar ideas.