Pienemann, ManfredKeßler, Jörg-U.Itani-Adams, Yuki2015-12-081367-0069http://hdl.handle.net/1885/29546In this article we utilize a developmental perspective as a metric for the comparison of bilingual language ability. In particular, we utilize Processabilty Theory (Pienemann, 1998a, 2005) which provides a psycholinguistic metric for developmental schedules of any given language. We demonstrate this approach to the cross-linguistic measurement of language development on the basis of Itani-Adams' (2007) study of bilingual (Japanese-English) first language acquisition.Keywords: bilingual language development; cross-linguistic metric; developmental perspective; levels of processability; Processability Theory; psycholinguistic metric201110.1177/13670069103800372016-02-24