This I)aper presents an implemented multi-tal)e twolevel model capable of describing Semitie non-linear morphology. The computational fl'arnework behind the ettrrcnt work is motivated by [Kay 1987]; the fimnalism presented here is an extension to the formalism reported by [Puhnan art(1 Hepl)le. 1993]. The objectives of the current work are: to stay as close as possible, in spirit, to standard two-level morl)hology, to stay close to the linguistic description of Semitic stems, and to present a model which can be used with ease by the Semitist. The. Imper illustrates that if finite-state transducers (FSTs) in a standard two-level morphology model are replaced with multi-tape attxiliary versions (AFSTs), one can account for Semitic root-andq)attern morphology using high level notation.