​According to James Fallow's checklist Seattle's falling short.  Danny Westneat editorializes in the Seattle Times.

So according to the Seattle 2035 Development Capacity Report, "Based on current zoning, DPD estimates that the city has development capacity to add about 224,000 housing units."  According to the HALA website, Mayor Murray wants to add 50,000 housing units in the next 10 years.  So there's plenty of capacity with current zoning to meet that goal, right?  

            - Carolee Colter and John V. Fox       
                   reprinted from Pacific Publishing newspapers Jan 2016 edition

Last November, the Seattle City Council approved a decision agenda that includes consideration in 2016 of upzones for every neighborhood in Seattle. It’s all part of Mayor Ed Murray’s so-called affordable housing plan, better described as a colossal giveaway to developers and a blueprint for the continued gentrification and displacement of low-income people from our city.
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But City Councilmember Michael O’Brien has gone one step further with proposals that would eliminate nearly all restrictions on mother-in-law apartments and backyard cottages in single-family zones — dubbed respectively, “accessory dwelling units” (ADUs) and “detached accessory dwelling units” (DADUs).

Recently a coalition, calling itself “Growing Together” made up of some advocates, developer sponsored groups, and a few unions announced its support for the Mayor’s HALA plan.  Characterizing it as a “grand bargain”, these groups have given their support to the key component of the plan calling for upzones across our city and more tax breaks to developers, provided that in return for these added benefits, developers also would be required to set aside some low income and affordable housing in their projects (less than 10 percent of total units) or pay in lieu of fees to be used for low income housing built elsewhere.