Abstract :
A definition of the term `design´ and its application to real time software, is given. A group of well known software design methods are analysed, including: Yourdon, SSADM, CORE, JSD, HOOD, MASCOT3. The author concludes that most design methods ignore architectural design, attempt to bypass it, or have just a single form of it. MASCOT and HOOD are the only two which address architectural design directly. Of these, HOOD provides only a limited subset of MASCOT. MASCOT itself has potential for enhancement to enable it to cope with the very largest of embedded real time systems