While they succeeded in giving lower-income families a place to live in the drive to provide popular housing, this system also led to the creation of suburban ghettos, with a problem of disrepair. There has been a long-term problem of gradual impoverishment of social tenants There, deprived strata of the population, mostly of immigrant origin and suffering massive under-employment, might in the past have been left to simmer away from the more affluent urban centres, sometimes becoming rife with social tensions and violence. This affects a minority of social housing but has a high profile and still produces serious tension.