As a shift occurs from single residential development to higher density development, it is timely to consider how to maximise the benefits of increased population density while minimising any harm. This literature review into the impact of density on health concludes that if planned effectively, increasing population density has the potential to produce numerous benefits to the environment and the community. However, despite good intent, it is easy to get this wrong without careful consideration. 

The debate about density in Australia exists in a context of increasing pressures on population growth and fuel prices; housing affordability; growing recognition of the need to increase public transport, conserve the natural environment and reduce carbon emissions; and the need for preservation of arable agricultural land to retain Australia's food security. 

Confronted by the potential for rapid population growth in the next four decades, state and federal governments are recognising the need to rethink the way populations are housed and mobilised. 

Urban and transport planners have attempted to categorise the urban design features required to encourage more walking, cycling and public transport use into the five D s: density, diversity, design, distance to transit and destination accessibility. At the top of the list is density. Without a minimum threshold of population density, public transport and local shops and services are not viable, nor are there sufficient populations to create vibrant local communities. Hence, from a health and sustainability perspective, the need to increase population densities seems inevitable. 

The evidence suggests that the success or otherwise of the implementation of policies to increase population density depends on three main factors: 

• the building (i.e. its location, construction, design, management and maintenance) 
• the socioeconomic and cultural make-up of residents and the local neighbourhood; and
• the quality and amenity of the neighbourhood environment in which higher density housing is located.