On 3 December 2008, the Commission published its 'Guidance on the Commission’s Enforcement Priorities in Applying Article 82 EC Treaty to Abusive Exclusionary Conduct by Dominant Undertakings' (“Guidance Paper”), which essentially sets out the Commission’s enforcement priorities with respect to exclusionary abuses. In line with the approach already taken in the fields of Article 81 EC and merger control, the Commission, through its Guidance Paper, has vowed to take a more effects-based approach to exclusionary abuses by dominant undertakings. The Guidance Paper is not intended to be a statement or interpretation of the law, but instead lays out the Commission’s 'enforcement priorities' with respect to Article 82 EC. This raises the issue whether the Commission is bound to apply the principles developed in the Guidance Paper or whether it can apply the more restrictive and formalistic principles contained in the Community courts’ case-law. In the context of the postal sector the advent of the Guidance Paper is particularly propitious in light of the crucial changes that are taking place. The recently promulgated Third Postal Directive ('Postal Directive') provides the legal basis for the full market opening of the postal sector, which is to be accomplished by 31 December 2010. A corollary of the abolition of any remaining, exclusive or special rights is that new possibilities for increased competition in the postal sector will be created. At the same time, however, the removal of the reserved sector is likely to increase the frequency of claims by entrants that incumbent postal operators are engaging in abusive behavior to maintain their market power in liberalized markets. With this in mind, the Guidance Paper provides dominant (postal) undertakings with a set of parameters within which they can assess conduct addressed in it i.e. exclusive dealing, tying and bundling, predatory practices, and refusal to supply.