The devastating Syrian civil war that began after the Arab Spring in 2011 has reminded the international community of the many consequences of civil war. However, this conflict is simply one of many ongoing conflicts around the globe. Civil war has a number of effects on individual lives, the country experiencing the conflict, as well as the international system more broadly. The humanitarian costs of civil war are steep. Individuals are negatively impacted by civil war in a myriad of ways. Three main areas of research are of interest: mortality, physical and mental trauma, and education. Several factors increase the number of deaths in a civil war, including a lack of democracy, economic downturns, and foreign assistance to combatants. Even if civilians survive conflict, they are likely to endure trauma that affects both mental and physical health. Strong evidence indicates that civil war spreads infectious diseases and severely diminishes life expectancy. Mental health is also likely to suffer in the face of conflict, as individuals often must overcome debilitating trauma. Finally, children are particularly susceptible in civil war settings. Children are often unable to continue their education as a consequence of civil war because combatants often target schools strategically or the state is unable to fund education as a result of funneling resources to the conflict. Civil wars also pose a number of threats to the state itself. First, a state that has experienced a civil war is much more likely to have another civil war in its future. Conflict recurrence has been explained through the type of settlement that concludes the initial civil war, institutions that may prevent recurrence like proportional representation, and the role of third parties in providing peace-ensuring security guarantees. Beyond recurrence of war, scholars have looked at the impact that civil wars have on state-level institutions, including democratization. While most state-level effects of civil war seem to be deleterious, there may also be positive effects, specifically in terms of female representation. Civil war in sub-Saharan Africa has been shown to increase the number of female representatives, perhaps providing an avenue for gender equality. Civil wars have ripple effects that impact neighboring countries and the international system more broadly. Proximate states are often challenged with an influx of refugees that may burden social programs or facilitate the spread of diseases and illicit arms. However, positive consequences of hosting refugees may include trading opportunities or economic growth from remittances. Moving beyond proximate states, civil wars have consequences for the entire globe. For example, civil wars have been demonstrated to spur international terrorism. The civil war literature has explored the various effects of conflict at the individual, state, and interstate level.