Ever since the EU was established the union has had as an objective to secure the peace in Europe. To this end the step by step integration of new members into the union was a part of the grand strategy already from the start. since the European Union was established there have been five enlargements and still there are more countries knocking on the EU-door. The basic idea behind the enlargement is the old devise that democracies do not go to war against each other and that the integration of new member states increases our common security. The enlargements that have taken the union from 6 to 27 Member States can be understood in a context of yesterdays´ treats becoming tomorrow´s members. For example, with almost every enlargement critical voices have been raised that the joining countries are to internally instable and that they will be portals for e.g. organised crime and illegal migration. Even though each enlargement has been widely debated the Eastern enlargment fin 2004 and the possible future enlargement to Turkey have without doupt been mostly debated and rewritten from a security dimension. Each enlargement has change the union - not only in geopolitical terms resulting in new neighbours, but also when it comes to priorities. Something that is highlighted with regard to future enlargements is how a potential disappointment among those remaining outside the community has to be handled and how a need for new partnerships will emerge in order to counteract a hard deviding line between those inside and those outside.