The cy-près doctrine ( SEE-PRAY; Law French, lit. 'so close', modern French: si près or aussi près) is a legal doctrine which allows a court to amend a legal document to enforce it "as near as possible" to the original intent of the instrument, in situations where it becomes impossible, impracticable, or illegal to enforce it under its original terms. The doctrine first arose in the English courts of equity, originating in the law of charitable trusts, but it has since been applied in the context of class action settlements in the United States.

An example of the doctrine's application is found in the Massachusetts Supreme Judicial Court case Jackson v. Phillips, where the testator, Francis Jackson, created a trust to be used to "create a public sentiment that will put an end to negro slavery in this country". Four years after Jackson's death, slavery was abolished by the Thirteenth Amendment, nullifying the express purpose of the trust. Some of Jackson's family members attempted to dissolve the trust in order to collect its proceeds, but the court disagreed, invoking cy-près and finding that Jackson's intent would be best served by using the trust "to promote the education, support and interests of the freedmen, lately slaves, in those states in which slavery had been so abolished".