The present study adopts a generative theoretical approach and analyzes a number of phonological and morphological rules in Akkadian, especially: a- EPENTHESIS, i - ADD , VOWEL DELE TION, VOWEL SHORTENING , VOWEL LENGTHENING , and FEM ININE SUFFIX SELECTION. Where necessary, the rules are motivated, described in detail, and reformulated. It is shown that all these rules are subordinated to constraints on Akkadian syllable structure. The Akkadian syllable may have no more than three segments (with the possible ex ception of a word-final syllable having a long vowel), and phonological rules eliminate overweight syllables, or produce well- formed ones. Sumerian influence seems to have engendered VOWEL DELETION in Akkadian, but the constraints on syllable structure curtail its applica tion. Related issues such as stress, orthography, and Assyrian VOWEL HARMONY are also treated.