At present the English law recognizes the principle of unjust enrichment, but it has not yet recognized any generalized right to restitution in every case of unjust enrichment. For example, a restitutionary claim for services has been extended to include the services freely accepted even though there was no initial request, and in some cases to the person who mistakenly discharges another's contractual or statutory duty without the other's knowledge. In the case of economic duress which often takes the form of the refusal to perform existing contractual obligations unless further benefits are conferred, the United States courts usually rule that the threat to break the contract is in itself a wrongful act. However, English courts have not reached a final view on this question. The third case discussed that of restitutionary claim arising from the breach of another's confidence, is also controversial. Consensus has not been reached as to the definition of 'confidential information,' and the case law is still undeveloped. A brief history of the English law of restitution, footnotes, and sample cases from the United States, Australia, Canada, and Great Britain, are included.