The new version of the ISO 9000 standard is presented as a system nearer to total quality management (TQM) than the old norm. Given the positive effect that TQM has had upon companies' performance, the new ISO could be a good opportunity for companies to attain better results. In this article the authors used case-study methodology to analyze future implications of ISO 9000:2000 for companies' performance. The way changes in the standard are being applied by Spanish companies suggests that the new ISO will not constitute a radical change. Alongside these findings, the authors looked into improvement in operational and financial measures derived from the implementation of the new standard, compared with ISO 9000:1994. Both the way in which the changes are being managed and the measures of performance improvement lead one to think that the new standard will not contribute to better company management. These bad ISO 9001:2000 results could only be different if firms adopt the changes seriously and do not merely try to add new lines to their quality manual.