A "one-size-fits-all" system of planning controls is unrealistic. Credit:James Alcock 1. Adopt an inclusionary housing law Sydney's recent property boom has provided enormous financial benefits to homeowners and private developers while pushing poorer families further down the housing affordability ladder. It is now time to even the scales. Inclusionary housing, or inclusionary zoning as it is known in the US, requires developers of large residential projects – say, 20 units or more – to set aside a fixed percentage of units – say, 15 per cent or so – for low- and moderate-income households. Participating builders may be granted density bonuses or other planning concessions. Studies in the US – where about 200 local governments have adopted such laws including, most recently, New York City – have found no adverse effects on overall housing prices or construction levels.

Sydney needs better co-ordination of different transport modes. Credit:Daniel Munoz 2. Implement true multi-modal transportation planning Congestion is an inevitable by-product of growth. Credit is due to the current NSW government for facing up to the region's transport investment shortfalls, but in the future, it must do so in a smarter and more multi-modal manner. Road projects like WestConnex may be needed, but they should only be considered as part of a larger portfolio of mobility-enhancing investments, including trains, light rail, buses, and transit-oriented development. The best way to achieve this is to move beyond simply co-ordinating different modes and services, as the Transport for NSW agency cluster does, to true multi-modal planning. For practical models, the NSW government might look to Freiburg, Germany; or to the Metropolitan Transportation Commission in the San Francisco Bay Area.

3. Improve the public realm I live in Glebe, and constantly marvel at the quality of its public realm. The big and little interconnected parks and reserves, the green byways, the small pedestrian alleys, the way that buildings frame but don't crowd the sidewalks – all of these combine to make a neighbourhood that is comfortably livable. And have some of Sydney's highest property values to boot. Today's large development projects are mostly lacking in such amenities. Large developers operate from a financial template, and since there is no easy way for them to monetise the benefits of public realm amenities, they rarely include them in development proposals unless forced to by government. Unfortunately, in their rush to maximise the velocity of new development, the NSW government and many local councils are giving short-shrift to the public realm. There are many ways to include Glebe-type public realm amenities in today's development projects if someone takes the time and care to do so. Vancouver is a good example. 4. Cumulative impact assessment

The costs and benefits of growth are inherently asymmetrical. Larger units like states and regions reap most of the benefits of growth in the form of jobs and taxes, while local councils and neighbourhoods are left to deal with the costs. The problem is that no one seems to be in charge of looking at the bigger picture. The solution to this problem is something called cumulative impact assessment. Cumulative impact assessment involves analysing the traffic, environmental, and social impacts of large development projects on top of the impacts of other recently-approved projects. By looking at the cumulative impacts of multiple projects, not just each project in isolation, state and local officials are in a much better position to negotiate appropriate measures to lessen those impacts. 5. Planning for growth corridors and heritage neighbourhoods

Metropolitan Sydney is now so large and diverse, and is home to so many different communities, that a "one-size-fits-all" system of planning controls is unrealistic. Different development approval systems work better or worse in different communities. For example, in older neighbourhoods where the existing scale and design of historical buildings adds tangible community value, the responsibility should be on the developer to demonstrate that their proposal is not likely to be harmful, and not on the community to demonstrate that it is. In a designated growth corridor, by contrast, it might be the developer who has the lesser burden of proof. If set forth in a transparent manner, this "horses for courses" approach would improve the quality of development in growing communities while also protecting heritage communities. All that would be required is for communities to get together to articulate their roles in Sydney's collective future. The recent establishment of the Greater Sydney Commission represents a unique opportunity to do just that. John Landis is Crossways Professor of city and regional planning at the University of Pennsylvania. He was a visiting scholar at the Henry Halloran Trust at the University of Sydney.