Hebrew, as other ~emitic languages, has a rich morpl1ology, observable in part by the complexity of verb inflections. The primary base of verbs in Hebrew is the past third singular form of tlfe verb. From this base, some twenty eight different inflected forms can be created according to tense, per~on, gender and number. Traditionally, inflection tables were used to describe the various inflected forms derived from the verb 'base. Research done by Oman has managed to describe the verb inflection process using the principles of Generative Grammar. In' this approach, inflCfted verb forms are viewed as constructs of the form preftx+base+sufftx. Verb inflection is described as a s~ries of sequentialpperations. The first stage converts the primary verb base to a secondary'base, when the secondary base is not the same as the primary base. Secondly, the appropriate prefix and/or suffix are concatenated to the base. Thirdly, several morpho-phonemic changes due to the affix concatenation occur. Algorithms for both generation and analysis according to these principles have been developed. The formalism developed by Koskenniemi, known as Two Level Morphology, proposes describing the morphology of any na,turallanguage by a set of lexicons and a set of Two Level rules, which act in parallel, and transform directly between the lexical and s~rface representations of a word. Thi~ alternative formalism has been used to describe the mOrPhology of several languages, including the major European languages. In our work, we examine the applicability of Two Level Morphology to the description of Hebrew verb inflection. We consider how to apply the Two l~vel framework to the stages of the inflection process of the previ9us approach.We show that the Two Level model can adequately handle the concatenation of the affixes to the verb base, and the resulting morphophonemic changes that occur. However, the first stage of inflection, namely the conversion of the primary base of the verb to the secondary base, is difficult to describe in a natural way using Two Level rules. This requires that the various verb bases be kept in the lexil;on system. We propOse a modification to the model that can solve this problem. In the course of our .work, we created a new implementation of the Two Level model written in PROLOG. In our implementation, Two Level rules are converted directly into PROLOG predicates, making \he use of the finite state automata of the original model unnecessary. We also propose a structural change in the Two Level lexicon system. An outline of our implementation is presented. T ec hn io n C om pu te r Sc ie nc e D ep ar tm en t T eh ni ca l R ep or t C S0 51 3 19 88