“Housing directly affects whether harm reduction services can even reach people”: an interview with Layal Bou Harfouch and Christina Mojica
As with all complex societal problems, there is no silver bullet for combatting the overdose crisis. That’s certainly true for harm reduction, which aims to empower people to reduce the harms of behaviors that have risk, without requiring or demanding that individuals be abstinent from those behaviors. Harm reduction was never intended to be delivered in a vacuum, divorced from the other complex personal and societal factors that impact people’s well-being. But by weaving harm reduction thinking into interconnected issues like behavioral health and housing, we can make big, complex problem-solving efforts more humane and more effective.
One example of this kind of integrated thinking is evident in a recent commentary on “bad housing policy” from Reason Foundation analysts Layal Bou Harfouch and Christina Mojica. Bou Harfouch and Mojica present harm reduction not as the solution to our overdose and homelessness crises, but as an essential element in both philosophy and practice when we address these challenges. We talked to Bou Harfouch and Mojica about their work.
Jessica Shortall: In your commentary, you talk about how homelessness and substance use disorders are “deeply intertwined.” I think the general public—and some policymakers—assume one is fueled by the other. Is that what the evidence shows us?
Layal Bou Harfouch: The relationship is more cyclical than linear. Unhoused people are disproportionately impacted by substance use, but it’s also true that being unhoused makes managing any health condition—including addiction—significantly harder. We see clear evidence that housing instability increases overdose risk, and that people who use drugs often avoid services out of fear of being punished or turned away. That’s why it's so important to understand drug use in context—not just as a cause or effect of homelessness, but as factors that deeply shape each other.
Christina Mojica: Exactly. From a housing policy perspective, the data are clear: Restrictive land use regulations and limited housing supply are major drivers of higher housing prices and hence of homelessness. Once someone loses access to stable housing, health outcomes deteriorate and the risk of overdose rises sharply. These crises don’t exist in isolation—they reinforce one another. But both are rooted in deeper systemic failures, especially the ways we block or delay the production of affordable and accessible housing.
Shortall: You talk about how “government mismanagement” of housing and development policies contributes to a housing shortage for vulnerable people. How do you get from that insight to talking about harm reduction?
Mojica: Because how we zone and regulate housing development directly determines who has access to housing—and who doesn’t. Restrictive land use policies like excessive areas of single-family only zoning, excessive setback requirements, high fees, expensive code requirements, and parking mandates make it nearly impossible to build affordable housing at scale. As a result, even when communities are ready to adopt housing-first or low-barrier approaches, there’s often no available housing to support those models. Harm reduction depends on stability, and you can’t stabilize someone’s life—or health—without a place to live.
Bou Harfouch: From the drug policy side, harm reduction is about meeting people where they are and giving them tools to stay alive and improve their health. If someone is using drugs and has no stable place to go, they’re automatically excluded from most traditional shelter options. That exclusion not only deepens their risk—it pushes them further from care. So when we talk about zoning or housing development, it directly affects whether harm reduction services can even reach the people who need them.
Shortall: What is “harm reduction-focused housing,” as you term it in your commentary?
Bou Harfouch: Harm reduction-focused housing means there are no sobriety requirements to get in, and services like medications for opioid use Disorder (MOUD), syringe access, and overdose prevention are available on-site or nearby. The Boston model we cited combined low-barrier housing with supportive services, and the outcomes were impressive—lower overdose rates, higher engagement in treatment, and more people transitioning to permanent housing. That’s what success looks like when you prioritize people’s health over abstinence.
Mojica: Structurally, these programs succeed because they aren’t constrained by the rigid rules that often make traditional shelters ineffective. A strong example is the transitional housing program in Hawaii, which combined on-site healthcare with housing and saw measurable improvements in health outcomes and reduced emergency room visits. But none of this is possible without housing availability. Without zoning reform and the capacity to build supportive housing at scale, these models remain isolated successes rather than scalable solutions.
Shortall: You’ve already touched a bit on the “rigid rules” imposed by taxpayer-funded shelters that create barriers to access to housing, which in turn can put people at greater risk. Can you give some examples of that dynamic?
Mojica: Traditional shelters often enforce curfews, sobriety requirements, and rigid behavioral rules that don’t reflect the lived realities of people experiencing homelessness. These policies may be well intentioned, but they end up deterring people from coming indoors. When individuals can’t meet the requirements, they’re pushed into encampments—unsafe environments that are frequently met with sweeps rather than sustainable solutions. It becomes a cycle of displacement without meaningful support or recovery pathways.
Bou Harfouch: From a harm reduction lens, these shelter policies can be incredibly harmful. People get swept out of encampments and lose access to medication or naloxone. For someone using opioids, that can mean painful withdrawal—or worse, fatal overdose. Rigid shelter models treat people’s drug use as a disqualifier, when in reality it’s a health condition that needs care, not punishment.
Shortall: You also make a connection to access to MOUD, something that we talk about here at R Street. Why is it so much harder for unhoused people to have steady access to these medications? Is anyone innovating in this space?
Bou Harfouch: Unhoused people face more barriers to MOUD than nearly any other group. Many programs require ID, insurance, or regular attendance that’s unrealistic if you’re living outside. Plus, shelters that prohibit drug use often don’t allow people on methadone or buprenorphine. That’s why co-located care—offering MOUD in housing settings—is so critical. The Boston program did this well. When you remove those barriers, you see higher treatment retention and fewer overdoses. It works—we just need to make it standard.
Mojica: And again, the structural barriers matter. You can’t bring MOUD to people without places for them to live. Yet zoning laws often prohibit converting vacant buildings into supportive housing or block multi-family housing altogether. These regulations stand in the way of exactly the kinds of integrated, health-focused innovations that programs like Boston’s have proven can work.
Shortall: How do zoning laws and other regulations impact the ability of local governments to implement an integrated, harm reduction-focused housing strategy? What are the impacts on taxpayers?
Mojica: Zoning laws are often the hidden culprit. Requirements like minimum lot sizes, parking mandates, and single-family-only zoning make it extraordinarily difficult to build affordable, supportive housing where it’s most needed. That limits supply, drives up costs, and makes it harder for cities to implement housing-first or wraparound service models. The taxpayer impact is significant. In San Francisco, housing one person can cost up to $47,000 annually. In Houston—where zoning is far less restrictive—it’s under $20,000. When housing policy enables rather than obstructs, we get more outcomes for fewer public dollars.
Bou Harfouch: Harm reduction thrives in low-barrier environments—but without physical housing, those environments don’t exist. From a public health perspective, restrictive land use policies don’t just inflate costs—they keep people sick, unstable, and more likely to overdose. When we fail to invest in housing as infrastructure for recovery, we end up spending more on emergency services, incarceration, and crisis care. It’s not just bad policy—it’s expensive policy.
You can follow Bou Harfouch’s and Mojica’s work here and here.