De Blasio's plan is to build 15,000 units over 15 years. Half of the units will be scatter site and the other half will be units located together in a building constructed for that purpose, called congregate supportive housing.
De Blasio announced his supportive housing plan in November 2015. Two months later, Gov. Andrew Cuomo announced his own plan to build 20,000 units of supportive housing statewide over 15 years. In the past, the city and state worked together on three joint supportive housing plans, called the New York / New York agreements.
Cuomo's plan is tied up until he and the Legislature can agree on a memorandum of understanding on how to allocate $2 billion of funding for affordable and supportive housing. The MOU was required under the budget deal negotiated between the governor and the Legislature in April.
De Blasio also released a report from his Supportive Housing Task Force on Monday. As reported by POLITICO New York in October, the task force is calling on the city to broadly target adults, families and youth and use a vulnerability index to target those who need the housing the most. This is a change from the previous supportive housing plan, where a specific number of units were targeted to very specific populations.
The report also calls on the city to allow people to be referred to supportive housing from places other than the Department of Homeless Services and calls on the city to proactively identify people who would benefit from supportive housing using data analysis.
See the report here