An article published by the Journal of the American Planning Association argues that single-family zoning "exacerbates inequality and undermines efficiency," and should be eliminated entirely.

An article by Michael Manville, Paavo Monkkonen, and Michael Lens, published by the Journal of the American Planning Association (JAPA), calls for the end of single-family zoning.
From the abstract:
R1’s origins are unpleasant: Stained by explicitly classist and implicitly racist motivations, R1 today continues to promote exclusion. It makes it harder for people to access high-opportunity places, and in expensive regions it contributes to shortages of housing, thereby benefiting homeowners at the expense of renters and forcing many housing consumers to spend more on housing. Stacked against these drawbacks, moreover, are a series of only weak arguments in R1’s favor about preferences, aesthetics, and a single-family way of life.
The full article, which is behind the journal's paywall, debunks the pro-single-family zoning arguments and appeals to planners to entirely abolish single-family zoning.
Update, December 10, 2019: The same issue of JAPA includes another article by Jake Wegman, titled "Death to Single-Family Zoning…and New Life to the Missing Middle," that makes a similar case against single-family zoning. On Twitter, Wegman said "it's long past time for the planning profession to stop defending the indefensible" in a thread promoting the opinion article.
FULL STORY: It's Time to End Single-Family Zoning

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Congressman Proposes Bill to Rename DC Metro “Trump Train”
The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).

The Simple Legislative Tool Transforming Vacant Downtowns
In California, Michigan and Georgia, an easy win is bringing dollars — and delight — back to city centers.

The States Losing Rural Delivery Rooms at an Alarming Pace
In some states, as few as 9% of rural hospitals still deliver babies. As a result, rising pre-term births, no adequate pre-term care and "harrowing" close calls are a growing reality.

The Small South Asian Republic Going all in on EVs
Thanks to one simple policy change less than five years ago, 65% of new cars in this Himalayan country are now electric.

DC Backpedals on Bike Lane Protection, Swaps Barriers for Paint
Citing aesthetic concerns, the city is removing the concrete barriers and flexposts that once separated Arizona Avenue cyclists from motor vehicles.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
Smith Gee Studio
City of Charlotte
City of Camden Redevelopment Agency
City of Astoria
Transportation Research & Education Center (TREC) at Portland State University
US High Speed Rail Association
City of Camden Redevelopment Agency
Municipality of Princeton (NJ)