You are quite correct. Little guidance has been given about what sort of people are envisaged. This relates to committees, the intention being to allow committees, which in future could be smaller if the school decides to go for a smaller governing body, to have access to a wider range of expertise, opinion and experience if they need it. But the governing body, not the committee, has to sanction the choice and can also remove the associate governor if need be.
The simplest case is a teacher with some particular expertise, or an outside expert with experience of the committee's function, finance being the obvious one, or marketing. Another category is a staff member who might not be eligible in his or her own right, for example the caretaker, if the school is not big enough to have a support staff representative by election, or already has its elected support staff member or members.
The governing body might then like to make the caretaker an associate member of the premises committee. I understand that a school student might be a suitable person to appoint if the governing body thinks fit.
The whole governing body must agree to the appointment, and it also decides whether to allow the person a vote. Even if it does so, the associate member can only vote when there is a majority of governors present at the meeting. Even a non-voting member, however, can contribute to discussion.
It isn't compulsory. You may think your committees are all right as they are.
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