Modifications to the Doctrine of Consideration:

1. A promisor who has promised to keep his offer open for a specified period is not at liberty to withdraw the offer before the expiration of that period on the ground that the promisee has not provided any consideration for the offer.
2. A creditor who promises, without receiving consideration, to forego the whole or part of a debt or to waive the performance of some other contractual or legal obligation can be held to his promise. The promise of waiver shall not be invalid as a contract by reason only of the absence of any consideration for it.
3. If one is legally bound to perform a legal duty, the performance, or promise to perform that act may be sufficient consideration.
4. It is possible for consideration to be supplied by someone other than the promisee. The beneficiary need not be the promisee. (Section 10 of the Contracts Act).
   (4 points at 1 mark each = 4 marks)