The Endangered Species Act gives the United States Fish and Wildlife Service the authority to exclude areas from protected species’ “critical habitat” when the benefits of excluding those areas would exceed the benefits of including them. This power is significant, because the regulatory burdens—and consequent loss in value—that follow upon a given piece of land’s inclusion in critical habitat can be significant. Therefore, one can imagine how the right to seek judicial review when the Service says, “Sorry, we’re not going to give your property an exclusion, even though the economic impact to you may be catastrophic,” is critical and should be non-controversial. Unfortunately, the lower federal courts have consistently ruled that landowners have no right to challenge the Service’s decision not to exclude their property. They reason that such a decision is committed exclusively to the Service’s discretion, because the statute says that the Service “may exclude,” not must exclude. In this article, published in the April edition of The Environmental Law Reporter, I argue that the courts are wrong and that judicial review should be allowed, at least to smoke out unconstitutional and irrational decision-making.