In common law legal systems, a trust is an arrangement whereby money or property is managed by one person (or persons, or organizations) for the benefit of another but is owned by the 'Trust'. A trust is created by a settlor, who entrusts some or all of his or her property to people of his choice (the trustees). The trustees are the legal owners of the trust property (or trust corpus), but they are obliged to hold the property for the benefit of one or more individuals or organizations (the beneficiary, a.k.a. cestui que use or cestui que trust), usually specified by the settlor. The trustees owe a fiduciary duty to the beneficiaries, who are the "beneficial" owners of the trust property.

The trust is governed by the terms of the trust document, which is usually written and in deed form. It is also governed by local law.

In the United States, the settlor is also called the trustor, grantor, donor, or creator.