The Javanese constraints, whose discovery is due to Uhlenbeck, exhibit a striking resemblance to the well-known root structure constraints found in Semitic languages. The similarity between the Semitic and the Javanese constraints argues strongly that we are dealing here with manifestations of universal aspects of tier structure. The consonantal elements of root morphemes are governed by homorganicity constraints closely paralleling those of Semitic in nature and extent. The cooccurrence data involving root-final consonants as they appear in Uhlenbeck are somewhat difficult to interpret since this position in Javanese has special properties and can be occupied only by a limited class of segments. The dependency of voicing, nasality, and retroflexion on the primary articulator features accounts for the incompatibility of homorganic consonants within morphemes. Consonants occupying the final position in a morpheme do not show consistent Obligatory Contour Principle-interactions with preceding tautomorphemic consonants. The assumption that the primary articulator features each occupy a separate tier finds support in the existence of long-distance OCP effects.