• This Subject Area Index lists all CALI lessons covering Contracts.
  • The Contracts Outline allows you to search for terms of art that correspond to topics you are studying to find suggestions for related CALI Lessons.
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A contract can contain many different types of promises, made up of both express and implied terms. Express and implied warranty terms are the subject of this lesson. For instance, when parties contract for the sale of goods, they have certain expectations about the goods to be sold. These expectations form the basis of warranties that arise under U.C.C. Article 2. That is, what has the seller agreed to sell?

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This lesson explores discharge of a contract by modification, both at common law and under the UCC. It can be run either as an introduction to the study of modification or as a review after you have completed your study.

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The Pre-Existing Duty Rule, Contract Modification, and Accord & Satisfaction

This lesson presents an introduction to the doctrine that the performance of a pre-existing duty, or a promise to perform such a duty, does not constitute a sufficient consideration to make a promise binding. Coverage includes: the performance of duties owed to the promise or third parties as consideration; modifications on one side of executory contracts; substituted contracts following rescission; executory accords; satisfaction; liquidated claims and offers to settle unliquidated claims.

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Modifications and the Pre-existing Duty Rule: Discussions in Contracts Podcast

The topic of this podcast is when contract modifications are not enforceable due to the pre-existing duty rule. Consideration is required to support enforcement of an agreement, including a modification to an agreement. In this podcast, we will look at when the pre-existing duty rule renders modifications unenforceable and when the modern common law rule and the rule of UCC § 2-209 permit enforcement of some modified agreements in the absence of new consideration. 

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Discharge of Duties: Discussions in Contracts Podcast

This podcast discusses a discharge of duties such that parties do not have to perform their contractual obligations and cannot demand performance under the other party's contract. Consideration is required to support enforcement of an agreement, including a modification of a contract resulting in a discharge of duties. This podcast will look at discharge by rescission, substituted performance, substituted contract, novation, and accord and satisfaction.

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Accord and Satisfaction: Discussions in Contracts Podcast

This podcast explains the concept of Accord and Satisfaction, with a focus on when an accord is formed and when performance under the accord results in a satisfaction. This concept differs from modification. With accord and satisfaction, one party has completed performance and the other party’s only obligation is to render its performance -- usually the payment of money. So the party who has performed is in the position of a creditor and the party who has not performed is in the position of a debtor.

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Impossibility, Frustration, and Impracticability

This lesson takes a look at the doctrine of excuse. In particular, we will look at the doctrines of impossibility, frustration of purpose and impracticability. Each of these doctrines excuses performance of the parties to the agreement. This lesson sets out the basic requisites for when courts excuse contract performance and evaluating those situations that merit excuse.

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Discussions in Contracts: Impossibility, Impracticability and Frustration Podcast

The topic of this podcast is impossibility, impracticability and frustration. Ordinarily we expect the parties to perform their contracts under the principle of pacta sunt servanda, meaning promises are to be kept. Contract law, though, does provide excuse for non-performance (meaning a party is not in breach) in the event of certain contingencies the nonoccurrence of which are basic assumptions of a contract. This podcast covers the three distinct grounds for excuse provided by contract law: (i) impossibility; (ii) impracticability; and (iii) frustration of purpose.

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Rescission is one of the ways in which contractual duties are discharged. This lesson discusses mutual rescission, rescission by one of the parties, and rescission as a remedy used by a court.