Using tenant-level data from fifteen states that represent more than thirty percent of all Low Income Housing Tax Credit (LIHTC) units, this paper examines tenant incomes, rental assistance and rent burdens to shed light on key questions about out largest federal supply-side affordable housing program. Specifically, what are the incomes of the tenants, and does this program reach those with extremely low incomes? What rent burdens are experienced, and is economic diversity within developments achieved? We find that more than forty percent of tenants have extremely low incomes, and the overwhelming majority of such tenants also receive some form of rental assistance. Rent burdens are generally higher than for HUD housing programs, but vary greatly by income level and are lowered by the sizable share of owners charging below maximum rents. Finally, we find evidence of both economically diverse developments and those with concentrations of households with extremely low incomes.