It seems we have some obligation to aid some others, but it's unclear why, to whom, and to what extent. Many consequentialists claim that we are obligated to help everyone to the marginal utility point but they do so without examining why we are obligated to aid others at all. I argue that we must investigate the basis of our duty to aid others in order to determine the nature and extent of our obligation. Although some consequentialists, notably, Kagan, Singer and Unger, present arguments intended to justify some of consequentialism's most counter-intuitive demands, they take the less counter-intuitive demands for granted and justify the steeper demands on the basis of their relevant similarity to the more palatable ones. The result of this strategy is that many of consequentialism's steeper demands free-ride on a superficial similarity with less taxing demands. This allows consequentialism to broaden our obligations beyond the reach of justification. I examine three possible explanations of our duty to aid others, namely, intuition, fairness and self-interest, and argue that none of them justify consequentialism's runaway demands.