NYC Department of Housing Preservation & Development | 25,642 followers on LinkedIn. Established in 1978, the New York City Department of Housing Preservation and Development (HPD) is the largest municipal housing preservation and development agency in the nation. The agency’s mission is to promote the quality and affordability of the city’s housing and the strength and diversity of its many neighborhoods. We do that by preserving affordable housing and protecting tenants, developing new affordable housing, enforcing the Housing Maintenance Code, and engaging neighborhoods in planning.