This case study explores school segregation prevention in Karlstads municipality. It adresses the division in Swedish schools based on students backgrounds and socioeconomic status, hindering education quality and limiting diverse interactions. Residential segregation and school choice contribute to the issue. Temporary solutions, like expanding existing schools, have been implemented, but a long-term approach is needed to maintain teaching quality and avoid overcrowding. The study acknowledges the impact of school choice freedom and the presence of private actors on the municipality´s ability to control student compositions. Within this context, the study examines the municipality´s capacity to control student flows through various measures such as reorganizing school units, constructing new schools, or adapting existing ones. Additionally, the study explores how localizing secondary schools can potentionally prevent school segregation. The study emphasize considering student composition and addressing segregation when planning school locations, particulary within the context of the proposed new secondary school in Karlstad.  The study finds that the free school choice limits municipality´s control over student flows and composition, leading to school segregation. Neo-liberal education reforms have created a market-driven school sector with private schools and free school choice. The responsibility for human development and success now lies with the local community and individuals. While attracting students based on status affects student flows and compositions, it does not prevent school segregation, as primarily resource-rich students change schools, reinforcing societal differences. Changing catchment areas, involving mixed residential areas, can partially prevent segregation but requires collaboration between politics, the municipality and the local community for legitimacy to overcome resistance. The study also finds that localization alone cannot prevent school segregation. Free school choice continues to hinder and limit the municipality´s efforts to combat segregation. Factors beyond the school´s control require actions beyond the the education sector. School choice based on socioeconomic status and student demographics increases dispaities and leads to homogeneous student compositions. While strategic localization can influence student compositions to some exent, it is insufficient when competition and school choice come into play. School localization cannot effectively counter schoolsegregation when students can opt out and attractiveness is crucial. However, ignoring free school choice is not an option for a successful investment in a new school. Factors like populaition growth and new housing in central areas contribute to increased demand, but the primary factors is students preference for central schools. Localization must consider this to compete for students and ensure sufficient capacity, benefiting students with choice while negatively impacting those remaining at unselected schools as their resources decrease.