Many of California's urban public schools, both traditional and charter, have seen dramatic changes in enrollment during the past two decades. These trends have contributed to fiscal and facilities issues for both types of schools, but they also represent an opportunity for better cross-sector collaboration. In our new report, "Changing Enrollment, Fiscal Strain, and Facilities Challenges in California's Urban Schools," we analyzed enrollment trend data for district and charter schools in six of California's urban centers: Los Angeles, San Diego, Oakland, San Francisco, Sacramento, and Fresno. In particular, we looked at how declines in district enrollment compared to growth in charter school enrollment within these communities. We found that the growth in charter school enrollment in these urban areas was equal to only 40 percent of the decline in district school enrollment from 2002-03 to 2018-19. Because school funding is predicated in large part on student enrollment, these declines contributed significantly to declining district revenues. However, it's also clear that larger trends of declining district school enrollment -- and not simply charter school enrollment growth -- drove the majority of change across these six urban school districts. While significant enrollment decline has left districts with excess capacity in facilities that charter schools should be able to access under Proposition 39, it remains difficult for charter schools to access affordable and stable school facilities. We examine several policy options to provide more transparent data on school facility usage and foster better collaboration between districts and charter schools to optimize the use of public facilities. [Funding for this project was provided by the California Charter Schools Association.]