The European Union's enlargement policy involves two main tracks: internal reform within the EU and progress of applicant countries towards joining. This process balances the need for expansion with the need for deepening integration. The EU has developed a method for enlargement based on differentiation and conditionality, creating an asymmetrical relationship between candidate countries and the EU. This shift is evident in the move from bilateral agreements to the use of Accession Partnerships as the main tool for pre-accession strategy.