This paper is a preliminary attempt to reconstruct the consonant system of Proto-East-Cushitic (PEC)one of the four branches of the Cushitic family. Data are taken from some twenty-odd languages including unpublished material on a variety of hitherto little known languages. After discussing a number of general problems raised by the phonological comparison of the East Cushitic languages, 23 consonants are reconstructed for the inventory of the proto- language and the evidence for the reconstructions is presented in the form of cognate sets and correspondence rules which map the proto-phonemes onto the individual reflexes. The method employed is that of comparative linguistics as traditionally employed in Indo-European linguistics.