Montgomery County, Maryland inclusionary zoning (1974–present)
In 1974, Montgomery County became the first US jurisdiction to require developers of new subdivisions to set aside a share of 'moderately priced dwelling units' for below-market sale or rent.
The program produced thousands of affordable units in market-rate neighborhoods over the following decades.
It became the national model for inclusionary zoning, though economists debate how much such mandates raise costs.
Greenville's plan ties development approval to below-market rentals, the same bargain Montgomery County pioneered a half-century ago.
