Cities are a unique blend of the fantasy of the powerful and the basic needs of the most vulnerable. Today’s cities are planned and developed with neoliberal urbanism being the guiding ideology where governments in conjunction with the most powerful sectors of the global economy, finance insurance and real estate decide how cities are developed. Neoliberal urbanism puts profit and global competitiveness above the needs of society and the environment creating unsustainable cities that are hostile to their most vulnerable citizens. This report examines how guerilla and tactical urbanism can create long-term sustainable changes in cities through the creation of urban interventions that reclaim the right to the city for all citizens. Three different cases of both guerilla and tactical urban interventions in the city of Barcelona were analyzed based on Jeffery Hou’s theory the three stage process of rupturing, accreting and bridging and Henri Lefebvre’s theory of the right to the city. Through analysis of these three cases, a guerilla intervention Can Masdeu, a hybrid guerilla and tactical urban intervention Can Batlló and a tactical urban intervention the Poblenou superblock pilot project; this report was able to determine how these types of interventions are able to be successful in creating long-term sustainable changes. It was found that the most successful urban interventions both guerilla and tactical must be able to create a strong social and or political movement related to the urban intervention. In order to create these strong social and political movements local residents and community members should be included in the design and building process of an intervention and the intervention should provide a use value for the local community. These interventions, which have strong movements backing them and are co-created by members of the community, have a better chance of creating change that is both long lasting and sustainable in comparison to neoliberal urban development.