This paper evaluates the impacts of low-income housing developments on the neighborhoods in which they are built. A discontinuity in the formula determining the allocation of tax credits to low-income housing developments as a function of neighborhood characteristics generates pseudo-random assignment in the number of low-income housing units built in similar sets of census tracts. Estimates indicate that a 30 percent increase in the tax credit generates an increase of approximately 6 low-income housing units on a base of 9 units per tract.