The rules of the Member States on the taxation of the foreign business income of companies, whether such rules are based on the fiscal principle of territoriality or on the principle of worldwide taxation, are in conflict with the objective of achievement of the internal market. This objective is indeed difficult to reach when it comes to the taxation of foreign income, given that the Member States are far from taxing companies doing business cross-border as if their operations were purely domestic. Areas of conflict include particularly the taxation of foreign profits, the deduction of foreign losses, the elimination of international double taxation and the attribution of profits to permanent establishments.