In administering a discretionary trust HSBC asks for guidance from the settlor, usually in the form of a letter of wishes addressed to the trust company. However this letter does not form part of the trust deed and is not legally binding on the trustee.

Guidance and a request to the trustee having no binding powers over the trustee. There may be multiple letters. They must be carefully drafted to avoid creating problems with the settlor or true settlor in the case of a grantor trust becoming a co-trustee. The trustee cannot be a pawn of the settlor or there is basis for the argument that there never was a complete renouncement of the assets. Sometimes referred to as a side letter.

A letter of wishes is a non-binding indication by the settlor of the manner in which he wishes the trustees to exercise their discretion in relation to a discretionary trust.