This Article offers a normative theory justifying the feasibility principle animating many environmental statutes. The feasibility principle avoids widespread plant shutdowns while maximizing the stringency of regulation that does not close plants. This principle offers a reasonable, democratically chosen response to distributional concerns and provides meaningful guidance regarding both maximum and minimum stringency. Pollution’s tendency to concentrate severe harms upon randomly selected victims justifies this approach’s stringency. Normally, widely distributed costs cannot justify failing to protect people from death, illness, and ecological destruction. But the principle’s constraints apply in the one situation where some initial restraint might be justified, when regulation threatens to produce widespread shutdowns that concentrate significant harms on individuals. The feasibility principle offers a rational alternative to CBA. Indeed, a comparison between CBA shows that the feasibility principle offers a more sensible way of taking cost into consideration than CBA does.