What motivates people to engage in activism against wealth inequality? The simple answer is, perceiving injustice. However, the current work demonstrates that these perceptions depend on political ideologies. More specifically, for political liberals who frequently question the fairness of the economic system, messages simply describing the extent of the inequality (distributive injustice) are enough to motivate activism (Study 1). For political conservatives, who are inclined to believe that inequality results from fair procedures, messages must also detail how the system of economic forces is unjust (procedural injustice; Studies 2 and 3). Together, these studies suggest perceiving injustice can galvanize social change, but for conservatives, this means more than simply outlining the extent of the inequality.