A letter of wishes is a non-binding indication by the 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...

 of the manner in which he wishes the trustees to exercise their discretion in relation to a discretionary trust

Discretionary trust

In British and Canadian law, a discretionary trust is a trust where the beneficiaries and/or their entitlements to the trust fund are not fixed, but are determined by the criteria set out in the trust instrument by the settlor. It is sometimes referred to as a family trust in Australia...

.

Letters of wishes are normally used in 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, although theoretically there is no reason why they should not be used in an inter vivos trust.

Letters of wishes are useful where a trust instrument

Trust instrument

A trust instrument is an instrument in writing executed by a settlor used to constitute a trust...

gives the trustees very wide powers and discretions. The letter of wishes principally sets out the manner in which the settlor wishes the trustees to exercise their powers and discretions, but is not binding on the trustees. All binding requirements must be contained in the trust instrument itself. It is also quite common for letters of wishes to make posthumous expressions of thanks or love to the objects of the trust.