According to act-consequentialism, only actions that make a difference to an outcome can be morally bad. Yet, there are classes of actions that don’t make a difference, but nevertheless seem to be morally bad. Explaining how such non-difference making actions are morally bad presents a challenge for act-consequentialism: the no-difference challenge. In this chapter we go into detail on what the no-difference challenge is, focusing in particular on act consequentialism. We talk about how different theories of causation affect the no-difference challenge; how the challenge shows up in real-world cases, including voting, global labor injustice, global poverty, and climate change; and we work through a number of the solutions to the challenge that have been offered, arguing that many fail to actually meet it. We defend and extend one solution that does, and we present a further solution of our own.