Everybody is talking about the major crunch in middle class housing — even after a decade long housing boom of historic proportions, in which 69% of households own their own home. The reason is quite simple: it is becoming financially and politically infeasible to build middle class housing in the two places most likely to absorb new construction — suburban greenfields and existing urban and suburban neighborhoods. In both cases, government policy is responsible.

In greenfields, new housing construction has been tagged as “sprawl.” Local citizens oppose it on the grounds that it is ugly, increases traffic, burdens local schools and infrastructure, and destroys attractive open space. Opposition efforts typically result in complicated regulations, expensive permits, interminable approval processes, and various efforts to buy and preserve open space. The result is inflated prices for suburban homes that would otherwise have been easily affordable to most Americans.

In built-up urban neighborhoods, residents oppose replacing familiar buildings with new higher-density housing as out-of-scale development in neighborhoods already experiencing overcrowded schools, congested streets, and a lack of parking. Some of this opposition is now uniting under the ludicrous term, “vertical sprawl.” Residents demand zoning that protects “neighborhood character.” The result is to reduce opportunities for development to the point that the price of housing in urban neighborhoods escalates.

With highways reaching capacity, developable land running out, and denser development becoming a political problem, it is growing harder and harder to build new housing for the middle class. Consequently, most development today is either single-family houses on small, expensive lots, or massive projects that must carry the costs of enormous fees, approvals, and various exactions demanded by local governments. Both cost too much for any but the rich.

There is plenty of blame to go round — residents who oppose change in their neighborhoods of any sort, mediocre developers whose poor products fuel local outrage — but in the end, the failure must rest squarely on the shoulders of local governments. Governments across the country have failed to fulfill their mission of providing the infrastructure and the public realm framework for new development. In many places, the only government contribution to the public realm of development is a highway. The rest — sewers, roads, and open space — is expected to come from the developers. As a result, infrastructures are soon strained to capacity, the public realm is hideous, and citizens — is it any surprise? — cry out for an end to development.

Some governments have attempted to compensate on the cheap by exacting concessions from developers to build parks, schools, and other public facilities. The result is that development becomes still more expensive (an expense inevitably passed through to home buyers), the facilities are minimal, and development pressure shapes the public realm and infrastructure, rather than vice versa.

It is time to set things right and start planning for growth once again. Governments must zone for the higher densities that make middle-class housing possible, and simultaneously they must make the investments necessary to shape that growth. In cities, that means investing in transit to defray added traffic. It means paying for schools and sewers and hospitals prior to development. And above all, it means investing in an attractive public realm framework that will provide open space for old citizens and new, and that will lure better development.

In suburbs, governments must lay out the parks, roads, water and sewer lines needed to shape a meaningful public realm that can knit together new development before vacant land is purchased for development. Governments must invest in the infrastructure of schools and other public facilities to support new residents.

How does one pay for these improvements? The simple answer is that these are not expenditures but investments, and the dividend they yield comes in the form of increased tax revenue from developed property, which can pay the debt service on the bonds issued to cover the costs of these initial public investments.

These public improvements not only encourage development, they make development politically acceptable. Most citizens who oppose growth do so because they are so displeased with the growth that they see. But growth with adequate infrastructure and an attractive, usable public realm is a very different thing. In Atlanta, my firm proposed just such a set of public realm improvements in the form of the Beltline Emerald Necklace, a 23-mile trail and light rail loop connecting over 2000 acres of new parkland. Thanks to the active support of Mayor Shirley Franklin, within one year the city approved the financing to implement the recommendations and has already acquired a property that will become the city’s largest public park. The Beltline gained the widespread support of Atlantans because it offered growth with a high quality of life — growth that will make a better city.

Even with rising land prices, it is still possible to build decent, affordable housing at market rates, without government subsidies. In both cities and suburbs, developers can produce low- and mid-rise, stick-built multi-family houses and apartment buildings at a relatively low cost. These may not be the suburban dream of a house with a yard, but they could be good housing for working people, without costing taxpayers a cent. If set in a well-funded, well-designed public realm, the housing can also be very attractive.

This will not solve all our country’s problems of housing. It will not for example, provide housing for people of very low income — that is only financially possible with government housing subsidies. It will, however, produce housing for the middle- and working-classes — housing that is no longer being produced at anything like the quantities that are necessary to maintain high rates of home ownership.

Cities are evolving organisms by their nature. The future does not lie in trying to stop that growth, nor in a false dichotomy between city and suburb — both are different parts of the same organism. The promise of a brighter future lies in government investment in the public realm to shape that change. Only then can we create a future that everyone can afford.

Mr. Garvin is a professor of urban planning and management at Yale University and the president and CEO of Alex Garvin & Associates, Inc.