CISG Article 79 is a revised version of the exemptions clause in ULIS Article 74, with many significant modifications. For analysis of them, see Stoll in Commentary on the UN Convention on the International Sale of Goods, Peter Schlechtriem ed. (Oxford 1998) 601-603.
CISG Article 79 ULIS Article 74 1. A party is not liable for a 1. Where one of the parties failure to perform any of his has not performed one of obligations if he proves that his obligations, he shall not the failure was due to an be liable for such non- impediment beyond his performance if he can prove control and that he could that it was due to circumstances not reasonably be expected which, according to the to have taken the impediment intention of the parties at into account at the time of the time of the conclusion of the conclusion of the contract the contract, he was not or to have avoided or bound to take into account or overcome it or its to void or to overcome; in the consequences. absence of any expression of the intention of the parties, 2. If the party's failure is due regard shall be had to what to the failure by a third person reasonable persons in the whom he has engaged to same situation would have perform the whole or a part intended. of the contract, that party is exempt from liability only if: 2. Where the circumstances (a) he is exempt under the which gave rise to the non- preceding paragraph; and (b) performance of the obligation the person whom he has so constituted only a temporary engaged would be so exempt impediment to performance, if the provisions of that the party in default shall paragraph were applied to him. nevertheless be permanently relieved of his obligation 3. The exemption provided by if, by reason of the delay, this article has effect for the performance would be so period during which the radically changed as to impediment exists. amount to the performance of an obligation quite different 4. The party who fails to perform from that contemplated by the must give notice to the other the contract. party of the impediment and its effect on his ability to perform. 3. The relief provided by this If the notice is not received by Article for one of the parties the other party within a reasonable shall not exclude the time after the party who fails to avoidance of the contract perform knew or ought to have under some other provision known of the impediment, he is of the present Law or deprive liable for damages resulting the other party of any right from such non-receipt. which he has under the present Law to reduce the price, unless 5. Nothing in this article the circumstances which entitled prevents either party from the first party to relief were exercising any right other caused by the act of the other than to claim damamges under party or of some person for this Convention. whose conduct he was responsible.