Judi Barrett
A recent lawsuit challenging Cambridge’s inclusionary zoning ordinance has reignited a familiar debate: whether requiring affordable housing as part of new development is fair, legal, or effective. It’s an important conversation – but one that should be grounded in evidence, experience and an understanding of how housing policy works in Massachusetts.
Inclusionary zoning is not an experiment. It is a long-standing, widely used policy tool that has helped communities across the state – and throughout the US – create permanently affordable homes in places where market forces alone would not.
As planners with decades of experience working with cities and towns, regional planning agencies and housing partners on the design and implementation of these policies, we know what happens when inclusionary zoning is done well and when it is absent from zoning.
It Produces Needed Housing
Inclusionary zoning works. In Beverly, developments totaling 963 new units produced 91 affordable homes that would not have been built without the policy.
Jennifer Raitt
Mission-driven developers often exceed these requirements Cambridge’s inclusionary zoning, in place since 1998, has delivered more than 1,100 affordable homes. That’s been reinforced recently by a citywide Affordable Housing Overlay District that streamlines approvals and allows significantly greater density and height to help affordable housing developers.
Brookline’s program has been equally effective. By allowing on-site units or fee-in-lieu, the town leveraged $11.2 million in local trust fund investments into $186.6 million in affordable housing production and preservation between 2019 and 2024, supporting more than 300 new or rehabilitated homes.
Communities that do all they can to provide for affordable housing tap many options: Chapter 40B comprehensive permits, Chapter 40R “Smart Growth” Zoning Overlay Districts, the MBTA Communities Law, the Community Preservation Act, Affordable Housing Trust Funds and others. Cities like Cambridge, Newton and Lynn also receive and invest federal housing funds in affordable housing development. However, inclusionary zoning is almost always in the affordable housing toolbox.
Communities control the makeup of their population by the choices they make to control housing growth. By allowing additional density or flexibility and encouraging more types of housing, they create value. Inclusionary zoning ensures that some portion of that value is reinvested locally in the form of affordable housing, helping communities remain economically competitive, functional and fair. Inclusionary zoning helps teachers, custodians, healthcare workers, seniors and young families – not in the abstract, but through real homes they can afford.
Communities Must Calibrate Policies
At the same time, inclusionary zoning is not a one-size-fits-all policy. There is no single “correct” percentage that works everywhere, forever. Communities also need to think carefully about how to set the trigger that requires projects to comply, such as the size of a proposed development.
Inclusionary zoning should be calibrated to local market conditions, construction costs and affordability goals, and paired with incentives such as additional density, height, parking flexibility or expedited permitting to help projects remain feasible. Moreover, inclusionary zoning works best when applied to multifamily units or townhomes – housing types that are efficient to build.
And like any other land use policy, it needs to be revisited periodically as conditions change. For example, Beverly and Brookline have amended their inclusionary zoning ordinances at least twice.
Current Debate Asks the Wrong Question
This is where the current debate misses the point. Framing inclusionary zoning as either an unreasonable burden on developers or the sole solution to the housing crisis oversimplifies a complicated policy issue. The real challenge is how to design inclusionary zoning so it delivers meaningful affordability while supporting continued housing production.
There are other considerations, too: whether sufficient staff capacity exists in municipal planning departments to work with developers – especially developers of small projects – and how units created through inclusionary zoning will remain affordable in the long run.
In practice, predictable, by-right inclusionary zoning can reduce uncertainty for developers and communities alike. Over time, requirements are incorporated into land values, allowing projects to move forward with clear expectations. For municipalities, inclusionary zoning provides a reliable way to produce affordable housing without relying exclusively on public subsidies. It can also be a vehicle for creating affordable units that count toward a community’s 10 percent requirement under Chapter 40B.
Massachusetts needs more housing of all kinds. That includes market-rate homes and deeply affordable units. Treating these goals as mutually exclusive is not only inaccurate – it’s counterproductive. Inclusionary zoning is one of the tools that allows communities to pursue both at once.
The Cambridge lawsuit raises legitimate questions about policy design and legal frameworks, and those questions deserve thoughtful consideration. But we should not undermine a proven approach based on abstract arguments removed from on-the-ground results.
At a time when housing affordability is straining households, employers, and local governments alike, the goal should be clear: build more housing, and ensure that growth creates equitable opportunities for a broad range of residents. Inclusionary zoning, when designed well, helps do exactly that.
Judi Barrett is president and founder of Hingham-based Barrett Planning Group. Jennifer Raitt is executive director of the Northern Middlesex Council of Governments, the regional planning organization for the city of Lowell and its surrounding towns.
