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Unpublished Paper
Pacta Sunt Servanda -- Or Not
ExpressO (2012)
  • Richard S. Wirtz

Abstract Two of the important defenses to the enforcement of contracts are impracticability and frustration of purpose. In the American law of contracts, the general rule is that the promisor bears the risk that the contract may become more burdensome or less desirable to her, as a result of changes in circumstances for which she did not plan. In traditional terms, pacta sunt servanda: contracts are to be performed, come what may. The theory underlying the two defenses is that when an extraordinary circumstance renders a promised performance so vitally different from what was to be expected that it changes the essential nature of that performance, justice requires a departure from the general rule. In this article it is submitted that the law of impracticability and frustration, as it has evolved under the Second Restatement and Section 2-615 of the Uniform Commercial Code, is more confusing and uncertain than it has to be, and that it frequently and unnecessarily fails of its purpose. Modest changes in the rules that define those defenses will render outcomes in the cases in which the defenses are claimed significantly more predictable and more fair.

  • contract law,
  • impossibility,
  • impracticability,
  • frustration,
  • contract defenses,
  • contract remedies,
  • enforcement of contracts,
  • discharge of contractual obligations
Publication Date
April 24, 2012
Citation Information
Richard S. Wirtz. "Pacta Sunt Servanda -- Or Not" ExpressO (2012)
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