States, counties, cities, and local stakeholders are increasingly taking the lead on climate change assessments. The state of California is currently releasing its Fourth Climate Change Assessment, which is based on nearly 50 independent research projects spanning topics ranging from wildfires and habitat loss to electricity and natural gas system resilience. This 2-day workshop engaged people involved in all aspects of the California assessment as well as those involved in assessment efforts in other states to identify elements of success, shared challenges, and strategies for engaging key stakeholders.