ISO 9000 is a management standard that provides customers with assurance thu their registered suppliers have a consistent quality system to which they adhere. this paper draws on four sources to show how ISO 9000 can lead to performance improvement. 1)theories of induces innovation and improvisation 2) the literature on ISO 9000 3) a case study of a telecom company. we find that the extent to which ISO 9000 is associated with performance improvement depends on the level of its assimilation, and the degree to which an organization goes beyond the minimal requirements of the standard.