When cities gentrify, it can be hard for working-class and low-income residents to stay put. Rising rents and property taxes make buildings unaffordable, or landlords may sell buildings to investors interested in redeveloping them into luxury condos. In her engaging study The Politics of Staying Put, Carolyn Gallaher focuses on a formal, city-sponsored initiative--The Tenant Opportunity to Purchase Act (TOPA)--that helps people keep their homes. This law, unique to the District of Columbia, allows tenants in apartment buildings contracted for sale the right to refuse the sale and purchase the building instead. In the hands of tenants, a process that would usually hurt them--conversion to a condominium or cooperative--can instead help them. Taking a broad, city-wide assessment of TOPA, Gallaher follows seven buildings through the program's process. She measures the law's level of success and its constraints. Her findingshave relevance for debates in urban affairs about condo conversion, urban local autonomy, and displacement.