A trust instrument is an instrument in writing executed by a settlor

Settlor

In law a settlor is a person who settles property on trust law for the benefit of beneficiaries. In some legal systems, a settlor is also referred to as a trustor, or occasionally, a grantor or donor. Where the trust is a testamentary trust, the settlor is usually referred to as the testator...

 used to constitute a trust

Trust law

In common law legal systems, a trust is a relationship whereby property is held by one party for the benefit of another...

. Trust instruments are generally only used in relation to an inter vivos trust; testamentary trust

Testamentary trust

A testamentary trust is a trust which arises upon the death of the testator, and which is specified in his or her will...

s are usually created under a will

Will (law)

A will or testament is a legal declaration by which a person, the testator, names one or more persons to manage his/her estate and provides for the transfer of his/her property at death...

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Although in most legal systems there are certain formalities associated with settling a trust, most legal systems impose few, if any, strictures on the trust instrument itself. Historically, the concept of a trust is the intervention of the courts of equity to prevent a legal owner treating the property as beneficially his own; provided that state of affairs exists, a trust arises notwithstanding any lack of formality in relation to the form of the trust instrument.

However, notwithstanding the flexible approach taken by the law, characteristically the legal profession has taken an extremely formalised approach to trust instruments.