Although nearly two decades have elapsed since the International Organization for Standardization (ISO) announced the ISO 9000 series standards in March 1987, there have been few attempts to explore the reasons why certified firms may fail to maintain ISO certification. In this paper, survey data from certified firms in Taiwan are used to examine the differences between firms that maintain certification and those that do not in terms of the benefits that firms felt they had obtained from certification. Multivariate analysis of covariance (MANCOVA) is used in order simultaneously to assess group differences across the 16 multiple dependent organizational benefit variables, covaried for company size and certification motives. Our findings show that those certified firms that maintain certification gain more benefits from the standards than those that do not. This study also demonstrates that firms' motives for obtaining certification have an impact on the strength of the relationship between the maintenance of certification and the benefits gained. However, company size does not appear to affect the strength of the relationship.