This thesis examines the informal barriers experienced by highly skilled EU15 citizens (free movers) in Copenhagen. The focal point of the research is to gain a perspective on how free movers and Copenhagen co-construct a unique framework for integration. In this optic both the free movers and Copenhagen are agents of potential informal barriers, given their respective characteristics. Through an exploratory case study the research seeks to investigate how free movers perceive Copenhagen and what informal barriers to integration they experience in Copenhagen. The research is based on empirical data. Attention is drawn to the perceived informal barriers, but also to how the free movers'' own attitudes towards migration and settlement participate in the creation of informal barriers. Free movers'' freedom of movement is an essential element of their mobility, that they seek to maintain upon migration. However, freedom of movement and more permanent settlement in a new country can turn out to be mutually exclussive factors of intra-European mobility.