A document that does not comply with the Wills Act can be incorporated by reference into a will, provided it is in existence when the will is executed and is referred to in the will as being then in existence. However, if this is done, the document is treated as part of the will and becomes public. This would defeat the object, namely secrecy, so, can there be a valid trust based on informal instructions to the intended secret trustee? The courts have recognised such trusts as valid provided certain criteria are fulfilled but there is some disagreement about the rationale behind this and the exact status of the trusts.