Imagine travelling back to 1945 and telling an Australian that the country’s population would almost quadruple over the next 80 years.

Australia was home to just over seven million people at the end of the Second World War. Today, the national population count sits four times higher at 28 million.

Our postwar Australian would have stared at us in disbelief: “So much growth. You must have built so many new cities. New ports, universities, railway lines, and industrial centres must stretch across the country. Surely the Australian population is spread across a much wider network of large cities than it is today.”

“Not quite, mate. We squeezed most of the additional 21 million people into the same five cities that dominate Australia today in 1945.”

Today, roughly two-thirds of Australians live in Sydney, Melbourne, Brisbane, Perth and Adelaide. By that measure, Australia has the most concentrated settlement pattern in the world (ignoring city states like Singapore).

The Gold Coast is the great postwar exception. It is the only new major city. It grew from a collection of coastal settlements into a genuine metropolitan economy with around three-quarters of a million residents. It has its own employment base, universities, hospitals, tourism economy and urban identity.

The Gold Coast wasn’t technically a planned city. But allowing it to grow into a major urban centre was one of the smartest things Australia did during the postwar population boom. We should have built six Gold Coasts.

Instead, we added suburb after suburb to the edges of our existing capitals. Sydney and Melbourne spread across vast distances. Infrastructure struggled to keep up. Commutes became longer and longer. Well-located land near the office towers became scarce and extraordinarily expensive. This history lesson matters because Australia is likely to keep growing.

Nobody can say precisely when Australia will double and reach 56 million people. Fertility, migration, life expectancy, economics and politics will all influence the trajectory.

The exact year matters less than the direction of travel. Australia remains prosperous, safe and politically stable in a region containing billions of people. We use migration to fill skills shortages, support growth and soften the fiscal impact of ageing.

Continued population growth remains the most likely long-term scenario. Not planning for that scenario is irresponsible.

We should ask a straightforward question now: Where will the next 28 million Australians live?

Right now, we don’t have a serious answer.

Governments release population projections but rarely connect them to a national settlement strategy. Housing, transport, water, universities, employment and migration are debated as separate policy areas.

When population growth arrives, we respond by rezoning another patch of land on the fringe of Melbourne, Sydney or Brisbane. We build the houses first and spend the following decades trying to retrofit railways, hospitals and schools.

This is not planning. It is population growth followed by emergency infrastructure spending, often shaped more by short-term electoral pressure than by the national interest.

Australia needs a long-term (80-100 years) national settlement strategy designed around the possibility of a population twice its current size.

That doesn’t mean spreading 56 million people evenly across the continent – most of Australia isn’t suited to large-scale settlement. Water is limited, distances are enormous and many inland locations are exposed to extreme heat.

Nor should we move people away from cities simply because they are crowded or expensive. Large cities are productive for good reasons. Businesses share specialised infrastructure, suppliers and services. Workers have access to more potential employers, while employers recruit from a deeper talent pool. Knowledge travels more quickly between firms, universities and workers. Larger and denser labour markets tend to be more productive.

Our problem isn’t that Australia has big cities. It’s that we have allowed five cities to grow without allowing enough homes near their most productive locations.

When jobs and wages increase but housing supply barely responds, the benefit is capitalised into land values. Existing property owners win. New workers pay more rent, take on larger mortgages or move further away. Productivity gains are swallowed by housing and commuting costs.

The first part of a national settlement strategy must therefore be to fix the cities we already have.

Australia has long treated housing as a choice between detached homes and skyscrapers. We excel at building subdivisions on the fringe and towers in a few inner-city precincts.

What is largely missing is everything in between: Terraces, townhouses, courtyard apartments, and buildings of three to eight storeys – the ordinary urban fabric of many European cities. They provide enough density to support frequent public transport, local shops and walkable neighbourhoods without forcing families into high-rise towers.

We should allow three-storey housing across most established residential land, with taller mid-rise buildings along transport and commercial corridors. Major railway and metro stations should be surrounded by substantial housing, employment and services. This would allow millions more Australians to live within existing urban areas while making better use of roads, pipes, schools and public transport.

The development of the Gold Coast into a major hub is a rare success story.

Cool, let’s do it then! Urban planners would be on board in no time. Unfortunately, infill housing is expensive and politically difficult. Developing one square metre of infill housing can cost about twice as much as adding the same amount on the urban fringe, before infrastructure is even included. Tighter density is needed, but retrofitting existing cities this way is hard. Designing new cities around it from the start would be much easier.

The second part of the strategy is to make our major cities genuinely polycentric.

Sydney and Melbourne are now too large to depend so heavily on a single central business district. Commutes from the outskirts to the centre take too long. We need multiple complete employment centres containing universities, hospitals, government offices, cultural institutions, apartments, shops and high-capacity transport. Historic planning made secondary hubs harder by constantly expanding the main CBD – Melbourne added Docklands and Fishermans Bend while Sydney added Barangaroo. Strengthening the centre can slow the emergence of serious alternatives.

Now, Parramatta is moving in the direction of becoming a serious second employment hub – a very welcome development. Other centres such as Liverpool, Penrith, Sunshine, Monash and Dandenong should become genuine cities within cities.

The goal is not to scatter a few office towers through the suburbs. It is to create large, specialised employment ecosystems where people can live, work, study and access services, linked by dramatically better transport.

The third part of the strategy is to create a much stronger second tier of Australian cities.

The best candidates are not isolated inland towns. They are existing cities with strong economic foundations, attractive lifestyles and access to larger markets.

Newcastle, Wollongong, Geelong, Ballarat, Bendigo, the Gold Coast, the Sunshine Coast, Toowoomba, Townsville, Cairns and Bunbury could all absorb substantially more growth. These cities should not be treated as disconnected regional outposts, but as parts of larger city-regions.

South-east Queensland already stretches from the Gold Coast through Brisbane to the Sunshine Coast, with connections inland to Toowoomba.

Victoria could link Melbourne, Geelong, Ballarat and Bendigo. NSW could better connect Sydney with Newcastle, the Central Coast, Wollongong and Canberra.

Fast and frequent transport is essential, but railways alone will not create productive regional cities. A fast train that carries people into Melbourne every morning can simply turn Geelong or Ballarat into more expensive commuter towns. The aim must be two-way economic integration.

Regional cities need their own employment clusters, universities, hospitals, cultural institutions and corporate activity. Transport should enlarge their labour markets rather than drain them.
Australia should also build a limited number of new urban centres over the coming 80 years.

Where would people want to live? Largely near the ocean, especially along the eastern seaboard. Australians will remain obsessed with water and lifestyle. Coastal cities will continue to grow quickly, and new coastal centres will emerge. Hopefully they will be built with modern urban planning and a distinct Australian design language.

We must avoid the fantasy that government can simply draw a city on a map, build houses on cheap land and wait for an economy to appear. A viable new centre needs a reason to exist: A port, airport, university, defence precinct, renewable energy zone, advanced manufacturing cluster, special economic zone or major tourism economy. It also needs secure water, reliable energy and transport connections to established cities.

Most importantly, governments must acquire land and reserve infrastructure corridors before announcing where growth will occur. A railway station or rezoning decision can make private landowners rich overnight. Government then buys some of that land back at inflated prices for schools, parks and roads.

A national settlement strategy should capture more of this value for the public. Development corporations could acquire land early, install infrastructure, sell development rights and reinvest the uplift into transport and community facilities.

We also need to treat housing construction as a national productivity industry. The Productivity Commission has found that Australia builds far fewer homes for each hour worked than it did three decades ago. A country planning for millions more residents cannot rely on a fragmented construction industry with declining productivity.

Standardised designs, prefabrication, digital approvals, national occupational licensing and stable long-term building pipelines must all be part of the settlement strategy.

The mistake Australia made after WWII was not population growth itself. The mistake was failing to imagine the urban system such growth required. We almost quadrupled the population while relying on essentially the same group of major cities. The resulting scarcity of well-located land helped push housing costs to extraordinary levels. We now have the opportunity to do things differently.

The next doubling of Australia should transform the country from five sprawling capitals surrounded by a thin network of regional towns into a connected system of compact, productive city-regions.

It doesn’t matter whether Australia reaches 56 million in 80 or 100 years. What matters is that long-term growth remains the most likely future. Waiting until every projection is certain would guarantee that we repeat the mistakes of the past.

By the time the population arrives, the land will be developed, the corridors blocked and the infrastructure vastly more expensive.

Australia does not need a precise population target. It needs a plan for the country we are most likely to become.

Simon Kuestenmacher is a co-founder of The Demographics Group. His columns, media commentary and public speaking focus on socio-demographic trends and how these impact Australia. His podcast, Demographics Decoded, explores the world through the demographic lens. Follow Simon on Twitter (X), Facebook, or LinkedIn.