Elections are the basis for democratic legitimacy. They give citizens a way to hold their leaders accountable by voting contestants in to, or out of, office. A credible election is one that is characterized by inclusiveness, transparency, accountability, and competitiveness. While many focus on the specific event of election day, elections are actually a process made up of multiple components. Public confidence in each step of an election process is critical to the integrity of the election. In order for citizens to participate in, understand, evaluate and, ultimately, accept an election process and its outcome as representing their will, election data must be open to citizens. Over the last three decades, a global movement of nonpartisan citizen election monitoring has collectively mobilized millions of citizens around the world to participate in their countries' democratic processes as election observers.