Decided 25 years ago this spring, Lucas v. South Carolina Coastal Council, 505 U.S. 1003 (1992), departed from previous regulatory takings cases in pronouncing a concrete rule of takings liability — applicable in cases where an imposed restriction goes so far as to deny an owner all economically beneficial uses, or to render his or her property entirely valueless. Previously the Supreme Court had said that regulatory takings claims should be assessed under the amorphous balancing test set forth in Penn Central Transportation Co. v. New York City, 438 U.S. 104 (1978). And as late as the 1987 term, the Court had disavowed categorical rules. See Keystone Bituminous Coal Assn. v. DeBenedictis, 480 U.S. 470, 495 (1987). Accordingly, many commentators were critical of Lucas, on the view that the decision was fundamentally at odds with Penn Central’s much more flexible approach. Still, the most controversial aspect of Lucas’ new per se rule was in that it wholly discounted legislative judgments. This not only elicited strenuous dissenting opinions, but prompted near-vitriolic criticism from some scholars who expressed concern that the Court had placed private interests above the public interest, in a manner that might impede the government’s ability to address pressing public concerns through regulation. The most biting critics argued that Lucas had revived the ghost of Lochner v. New York, 198 US 45, 75 (1905). But as explained in this retrospective, these concerns have proven largely unfounded. Lucas did not seriously hamstring environmental regulation, let alone municipal land use planning. And, in any event, the Lochner analogy was improper from the outset because Lucas left undisturbed the general presumption, set forth in Village of Euclid v. Ambler Realty Co., 272 U.S. 365, 391 (1926), that land use restrictions will be upheld so long as they reasonably relate to the advancement of a legitimate state interest. Moreover, as discussed in greater depth within this article, subsequent developments have since placed both Lucas and Village of Euclid in their proper context. As would only be appropriate in a retrospective analysis, I consider the full implications of Lucas for the development of our modern regulatory takings doctrine. First, I explain that Lucas was a logical outgrowth of the Court’s seminal regulatory takings case in Pennsylvania Coal Co. v. Mahon, 260 U.S. 393, 413 (1922). Second, I evaluate subsequent developments that have minimized the practical impact of Lucas for landowners and land use planners. Yet, at the same time, I also suggest that Lucas was a significant step forward in the development a more sophisticated regulatory takings doctrine, especially in explaining that takings claims are assessed with reference to those rights enuring in the title to land — as defined by objective background principles ensconced in state law. Finally, I conclude that there remains a vital need for the Supreme Court to clarify lingering questions of essential importance in Lucas claims. Ultimately, I suggest that subsequent developments have underscored the need for more concrete guidance, and judicially manageable standards, for reviewing takings claims that do not fit squarely within the Lucas framework — i.e., “partial takings claims” wherein the authorities have imposed severe land use restrictions, while allowing the owner to retain some modicum of value in the land, or to maintain some modest development opportunity.