This paper explores a range of Foreign vocabulary in American Sign Language and demonstrates that there are ways of accounting for them without undermining the fundamental independence of a natural sign language. Arguments are made for a unified lexicon in which Native and Foreign vocabulary are arranged schematically as extending from a core to a periphery with gradations of conformity to phonological constraints on ASL forms. At the conclusion of the paper there is a brief review of issues concerning the presence of Foreign vocabulary in natural sign languages.