As part of my post-doctoral research I will present our ongoing research, exploring which role the private sector has in Umeå municipalities endevour to become a social sustainable city and thereby avoid the development of disadvantage areas with social problems and criminality. Building on Prof. Erikssons survey 2006-2020, we have explored a neighbourhood with postive development, a unique district which managed to turn around a negative development going from low- to middle high social capital. I will present our main findings: the involvement of private sector is the key factor, that explains the relatively fast development of a neighbourhood, further I will discuss which role the private sector and municipality have in building social sustainable society.