Does Inclusionary Zoning Work?

Economist: New Inclusionary Zoning Law Unlikely to Ease Portland’s Housing Crunch

When Oregon lifted its restrictions on cities creating inclusionary zoning laws, which require developers to include a particular number of below-market-rate units in new residential developments, it added at tool that could be used to address affordable housing issues.  However, inclusionary zoning can produce mixed results and there isn't general agreement that it actually helps affordable housing in the city as a whole, as discussed in this Willamette Week article. 

In remarks yesterday to the Northwest Chapter of the Urban Land Institute, Cortright cited research from other cities where inclusionary zoning has been implemented. The findings: inclusionary zoning does not produce enough new housing units to make a difference.
— Nigel Jaquiss, Willamette Week