Infill Philadelphia is a five-year initiative created by the Community Design Collaborative to promote workable, innovative design solutions to revitalizing older, urban neighborhoods.

Infill Philadelphia brings together design practitioners, community development experts, policymakers, funders and the media to address urban infill development—a significant neighborhood revitalization strategy for Philadelphia and older American cities.

Infill development sites are best characterized as neglected public spaces and clusters of vacant or nearly-empty buildings and land. Over time, these sites can obstruct community development plans and even threaten neighborhood stability and growth.

Infill Philadelphia is helping urban communities re-envision their neighborhoods, leverage existing assets, rethink the use of older spaces, and address the practical concerns of specific sites and the communities around them. The initiative is being implemented in three phases, each addressing a specific infill development opportunity. Each phase of Infill Philadelphia is sponsored by the Community Design Collaborative in partnership with nonprofit leaders in the field of community development.

The conceptual designs developed for Infill Philadelphia are created through a "design challenge", an intensive, interactive design process in which volunteer design firms work simultaneously to develop conceptual ideas for three real-life sites selected by community-based organizations.