The success or failure of slavery reparations will depend on causation. Many criticisms of reparations have focused on the attenuated nature of the harm, suggesting that modern claimants are not connected to slaves, that modern payers are not connected to slave owners, and that harms suffered by modern Blacks cannot be connected to slavery. This Article examines these attenuation concerns and finds that they come in three related but distinct varieties: Victim attenuation, wrongdoer attenuation, and act attenuation. These three components, defined in this Article, show themselves in a number of interrelated arguments. The Article then discusses how ideas about causation from the mass tort context can help address the problems of attenuation in slavery reparations. Mass tort cases have developed novel methods of showing causation, such as statistical evidence and market share liability, and these tools can be used in the reparations context. These concepts, if used within the reparations context, could help overcome attenuation.