Melbourne has more than 1.5 million private dwellings. About 9% of them are unoccupied, according to Census 2011. Of occupied private dwellings in Melbourne, 73% are separate houses, 15% are flats/units/apartments, and 12% are semi-detached/townhouses. With the rapidly growing population, there is obviously a need for more housing. There are two general housing development trends in Melbourne: 1) building more high rise apartments in the inner city and 2) more housing developments on the urban fringe. Each has its own advocates and critics.