It is essential for social workers to understand the magnitude and nature of this country’s affordable housing crisis and its implications for practice. The principal causes of the contemporary affordable housing crisis are complex. The demand for affordable housing is affected by increases in poverty and growth in the number of U.S. households. In addition to ordinary population increases, growth in the number of people needing housing also results from declining marriage rates and an increase in the average age at which people first marry, which postpone the combining of households.