Hartson, H. Rex2013-06-192013-06-191988http://hdl.handle.net/10919/19540It is generally agreed that some kind of separation is needed between the human-computer dialogue and the computational component of an interactive software system. This paper addresses two major issues:application/pdfenIn CopyrightTechnical reportTR-88-03http://eprints.cs.vt.edu/archive/00000088/01/TR-88-03_partial.pdf