In the case of McRae v Commonwealth Disposals Commission (1951), the High Court of Australia dealt with issues related to contract law, specifically focusing on the concept of unjust enrichment. The case involved the sale of a non-existent oil tanker by the Commonwealth Disposals Commission to McRae. McRae was led to believe that the tanker was located on a reef and spent considerable resources attempting to salvage it, only to discover that it did not exist.

The High Court addressed the issue of unjust enrichment by focusing on the misrepresentation and breach of contract by the Commonwealth Disposals Commission. The court found that the Commission had made a false representation about the existence of the tanker, which constituted a breach of contract. As a result, McRae was entitled to recover the expenses incurred in the futile salvage operation.

The court's decision highlighted that unjust enrichment occurs when one party is unjustly enriched at the expense of another, and restitution is required to prevent this. In this case, the court ordered the Commonwealth Disposals Commission to compensate McRae for the losses suffered due to the Commission's misrepresentation, thereby addressing the unjust enrichment that would have occurred had McRae not been compensated.

This case is significant in Australian contract law as it illustrates the application of the principle of unjust enrichment and the importance of accurate representations in contractual agreements.