I am the only person in our company authorised to book our board room.  It has been that way for years as it was always supposed to be available for shareholder/director use and as other people in the office might not be aware of when the shareholders are likely to want it has always gone through the Exec PA.  That way there is no embarrassment of being unceremoniously turfed out of the room as I know used to happen at one National Housebuilder in the UK! But I suspect we are unusual as most companies will have their meetings planned and diarised in advance whereas we chop and change ours at short notice.  And yes that means sometimes you can have a person desperately searching for a meeting room while the board room stands empty.