The ever higher levels of complexity exhibited by complex, domain-specific software systems have significantly increased the importance of a commonly accepted, clearly defined, and domain-specific set of design patterns and rules.We call such a generic software design framework a domain architecture. This paper presents GARM, A Generic Architecture Reference Model. GARM's focus is to identify the elements and concepts necessary to make a domain architecture specification complete and consistent, and to guarantee the specification will work in a consistent way with the related development process.We present a formal specification, in extended BNF, of GARM and discuss its constituting elements and concepts. A small example is used to illustrate the application of the GARM reference model.