Abstract: A chair system particularly useful for a dental office or other operatory wherein the head region of a subject is to be treated by a dentist or other operator, comprises a subject's chair for seating the subject in an upright position; an operator's chair for seating the operator in an upright position facing the subject; and a mounting for mounting the operator's chair at a higher elevation than the subject's chair such that the legs of the operator straddle the legs of the subject when both are seated in their respective chairs. The chair system further includes a vertically-extending barrier between the operator's chair and the subject's chair terminating below the head region of the subject when seated in the subject's chair, separating the operator from the subject but permitting free access by the operator over the top of the barrier to the head region of the subject.