Globalisation has had positive effects on the development of tax systems and has encouraged countries to engage in base broadening and rate reducing tax reforms. However, it has also created an environment in which tax havens thrive and in which governments may be induced to adopt harmful preferential tax regimes to attract mobile activities. Tax competition in the form of harmful tax practices can distort trade and investment patterns, erode national tax bases and shift part of the tax burden onto less mobile tax bases, such as labor and consumption, thus adversely affecting employment and undermining the fairness of tax structures.

The Report emphasises that governments must intensify their cooperative actions to curb harmful tax practices. To achieve this, OECD Member governments have developed "Guidelines on Harmful Preferential Tax Regimes". These Guidelines will discourage the spread of harmful preferential tax regimes and encourage countries with such regimes to eliminate them. To counteract both tax havens and harmful preferential tax regimes, Member governments have also agreed to pursue vigorously the implementation of the other Recommendations in the Report, including entering into a dialogue with non-member countries.