Subject to subsection (2), the persons whom the trustees may under section 11 authorise to exercise functions as their agent include one or more of their number.

The trustees may not authorise two (or more) persons to exercise the same function unless they are to exercise the function jointly.

The trustees may not under section 11 authorise a beneficiary to exercise any function as their agent (even if the beneficiary is also a trustee).

The trustees may under section 11 authorise a person to exercise functions as their agent even though he is also appointed to act as their nominee or custodian (whether under section 16, 17 or 18 or any other power).