The purpose of this Electoral Security Best Practices Guide (Guide) is to provide USAID's development professionals, as well as electoral assistance and conflict prevention policy-makers and practitioners, with a global over view of best practices in programming to prevent, manage, or mediate electoral conflict and violence. A "best practice" can be defined as a process, program, or method that produces results superior to others as measured by a set of objectives. Within the context of electoral security, a "best practice" can be defined as a policy, practice, or program intervention that has demonstrated measurable results in achieving electoral conflict prevention, management, or mediation. For the purposes of this Guide, best practices are organized as follows: 1) electoral phase; 2) thematic area; and 3) policy, practice, or program activity by state and non-state stakeholder. In order to inform this Guide, electoral security assessments were conducted in Guatemala, Afghanistan, the Philippines, and Burundi, employing the methodology described in USAID's Electoral Security Framework - Technical Guidance Handbook for Democracy and Governance Officers (Framework). These country cases present a diversity of electoral conflict profiles in perpetrators, victims, motives, tactics, locations, timing, and intensity. There are several overarching lessons learned from these assessments and associated research for this Guide. First, by identifying the underlying security, political, social, and economic vulnerabilities for electoral conflict to occur, early warning signs can be identified to focus planning for program interventions. Second, through establishing a profile of the threats, program responses can be specifically crafted to address the conflict emerging from these threats. Third, a history of electoral conflict can be a predictor of future electoral conflict. Therefore, previous threat profiles may have relevance for future elections. And fourth, comprehensive program responses should be multi-sectoral and can involve elections and political transitions, conflict management and mitigation, rule of law, civil society, media, women's empowerment, and security sector programs.