In October 2013, the California Civic Engagement Project (CCEP), in partnership with the Future of California Elections (FOCE), launched a research study examining California’s vote-by-mail ballots. This groundbreaking research is the first to provide a comprehensive analysis of the make-up of California’s unsuccessful vote-by-mail voters, as well as a wider examination of the composition of California’s 2012 vote-by-mail voters (beyond only unsuccessful voters). This research also identifies changes in the demographic composition of these voters during the last decade.