The first part of this chapter distinguishes war-related displacement from other types of population movements, including displacement due to communal violence, state repression, development, and natural disasters. It then unpacks the “black box” of war-related displacement by distinguishing between “collateral” displacement, “opportunistic” displacement, and “strategic” displacement. It then disaggregates strategic displacement into three subtypes – cleansing, depopulation, and forced relocation – and shows that they vary in orientation, targeting, and intended duration. The second part of the chapter introduces a new dataset on population displacement strategies in 166 civil wars from 1945 to 2017. It describes the relative frequency of these strategies across conflicts and over time and how they vary by perpetrator and types of civil wars. The dataset serves both descriptive and explanatory purposes. It shows that strategic displacement has been much more common in civil wars than previously thought and reveals important patterns in how, where, and when these strategies have been employed, which can be leveraged to explain why they occur.