In this report, we investigate how integrating components of oak woodlands into developed landscapes — “re-oaking” — can provide an array of valuable functions for both wildlife and people. Re-oaking can increase the biodiversity and ecological resilience of urban ecosystems, improve critical urban forest functions such as shade and carbon storage, and enhance the capacity of cities to adapt to a changing climate. We focus on Silicon Valley, where oak woodland replacement by agriculture and urbanization tells a story that has occurred in many other cities in California. We highlight how the history and ecology of the Silicon Valley landscape can be used as a guide to plan more ecologically resilient cities in the Bay Area, within the region and elsewhere in California. We see re-oaking as part of, and not a substitute for, the important and broader oak woodland conservation efforts taking place throughout the state.