In the dispute arising over Chinese measures regarding audiovisual goods and services，the United States' claimed that Chinese measures restricting sound recording distribution services are viola tions of the Chinese Schedule commitments，and accordingly，of Article ⅩⅧ of GATS.Guided by the “customary rules of interpretation of public international law”embodied in Vienna Convention on the Lawof Treaties，especially in Articles. 31 and 32，the DSU Panel and the Appellate Body in question supportthe abovementionedclaim，after they examine andclarify the ordinary meaning，context，object and purpose of the entry “sound recording distribution services”in Chinese Schedule.