In many countries, but not only in Europe, the collective agreement is strongly determined by extensions by governments. These administrative extensions extend the scope of collective agreements beyond their signatory parties – usually companies linked to the notification of employers` organisations and workers linked to trade unions who declare themselves – to all companies and workers in the sector where the agreement was signed. These results must be interpreted with some caution, as the debate is largely based on the supposed linear relationship between the duration of administrative delay and the effects of enlargements and employment growth. In response to questions about the role of administrative extensions in wage adjustment, the government, which took office in June 2011, temporarily suspended the granting of extensions with immediate effect, while preparing a reform of the procedures for extensions. This decision was taken as part of the structural reform package agreed between Portugal and the « troika » (EU, ECB and IMF). This package included a collective bargaining provision (« define clear criteria for the extension of collective agreements, » including « the representativeness of bargaining organizations and the impact of enlargement on the competitive position of unaffiliated firms »).5 The subsequent labour law reform of 2012 restored the renewal procedures, which were revised in two important ways. The first was to meet the criteria for representation. As a result, the extensions were conditional on the representation of companies by the employers` organisation, which represent a total of 50% of the employees in the sector concerned. The second amendment was that the extensions came into effect at the time of the administrative decision to extend and not at the entry into force of the collective agreement itself, i.e. the retroactivity was abandoned. Results based on the residues of the individual regression of basic log wages on job class dummies, which were reduced by type of business (linked vs. unrelated), collective agreement and year.