Launched in 2018, the Washington Housing Initiative identifies and acquires rental properties in neighborhoods facing rising property values in the Washington, DC area, and keeps a majority of the apartments affordable for households with moderate incomes. This report describes the Washington Housing Initiative and its potential contributions in the context of the region’s long-term housing challenges. It addresses four important features of the Initiative’s design, including moderate income targeting, affordable housing preservation, property acquisition in well-resourced neighborhoods, and long-term affordability. This report also explores other available housing preservation and production tools that reflect growing private-sector interest in addressing affordable housing concerns. The Washington Housing Initiative is not a substitute for expanded public sector investment in affordable housing, but can help fill a critical gap in the portfolio of regional efforts to create a housing market that serves all the region’s residents.