Mayor-elect Bill de Blasio’s support for affordable housing is critical to the future of New York, but not just because affordable housing means stable rents and mortgages for the city’s low- and moderate-income families. It is also a critical tool that the city can wield to help homeless persons get back on their feet, as well as to save lives by providing survivors of domestic violence and their families with long-term safety and stability. Yet, homeless persons, particularly survivors of domestic violence, struggle to access existing housing resources, an area where de Blasio can make a difference.

New Yorkers know they need affordable housing options; according to a poll released before the election, more than eight in 10 New Yorkers believed affordable housing is a top priority for the next mayor.

And they’re right. Affordable housing needs to be at the forefront of discussions between lawmakers, developers, and everyone who has a stake in New York City.

Low- and moderate-income families already struggle to make ends meet. One-third of families in New York City spend at least half of their income on housing, forcing them to make difficult tradeoffs between food, clothing, transportation and healthcare. An astounding 1.4 million New Yorkers rely on soup kitchens and food pantries to put nutritious meals on the table.

These already difficult experiences are exacerbated among the city’s most underserved and neglected populations. Every night, 64.060 New Yorkers sleep in a shelter or on the street. Homeless persons often cycle in and out of the city’s shelter system, unable to get back on track without the stability that real permanent affordable housing would provide them.

Almost one-third of homeless families in the shelter system are survivors of domestic violence with children whose lives are up-ended as their parents seek to escape abuse. Even worse, 80 percent of survivors who leave the emergency shelter system have no safe place to go. In fact, many survivors of domestic violence stay with their abusive partner because of fears of becoming homeless if they were to escape. For survivors with children this can be an especially difficult and emotional decision to make and could be made easier with more affordable housing options.

So what should be done? De Blasio’s affordable housing plan, in addition to encouraging the creation of new housing, should also address existing housing policies. For example, survivors of domestic violence in the Human Resources Administration (HRA) shelter system are not considered homeless and therefore are not eligible for the same housing resources as homeless New Yorkers in the Department of Homeless Services (DHS) shelter system.

Easy fixes to existing policies could give survivors equal access to permanent housing. These include making available the Department of Housing Preservation and Development’s (HPD) Section 8 and homeless set-aside units to victims of domestic violence using the HRA shelter system, and revising the criteria to gain access to New York City Housing Authority (NYCHA)’s Domestic Violence priority housing by adding a risk assessment tool and accepting more sources of documentation. Less than one-third of survivors in domestic violence emergency shelters meet the current criteria.

The application process for HPD and NYCHA housing should also be streamlined and made easier for survivors to ensure that they have a safe place to stay before their shelter stay expires. Finally, de Blasio should include in his housing plan a local rent subsidy, in partnership with New York State, to provide another bridge for families out of homelessness and into permanent housing.

The good news is that affordable housing is incredibly cost-effective and, according to the Independent Budget Office, allocating priority housing would save the city millions of dollars currently spent on costly shelters. The actual cost to house a family in a shelter for one year is $36,000, compared to an average of $12,000 per year in rent for affordable housing.

Affordable housing is also shown to contribute to positive health outcomes for children by providing their families with stability, and by freeing up resources that can be put towards their present needs and a better future.

For the children of survivors of domestic violence, the emotional turmoil can be traumatic and lead to educational delays, which can perpetuate poverty across generations as well as increase dependence on emergency and criminal justice services. Those consequences are much more expensive to the city than providing additional permanent affordable housing options.

Although Mayor-elect de Blasio made affordable housing a central element of his campaign platform, a substantial amount of uncertainty remains about what policies he will introduce as mayor. Beyond helping low-income New Yorkers, de Blasio has an opportunity to provide the city’s most neglected and underserved populations with safe and affordable housing options. On day one of his administration, through a combination of low-cost technical fixes to existing housing policies and new initiatives including a local rent subsidy, he can begin to break the cycle of homelessness and guarantee the long-term safety and stability of survivors of domestic violence and all homeless New Yorkers. Serving vulnerable New Yorkers is not only the morally right thing to do, but it is also a cost effective solution that will save the city millions of dollars. All the next mayor needs to do is act.