Abstract: An office space dividing system having at least first and second work stations having horizontally oriented work surfaces separated by a barrier panel having first and second sides and an opening in the panel which is adjacent to and above the work surfaces. A convertible panel is mounted in the opening of the barrier panel, for slideable engagement therewith. The convertible panel is operable between open and closed positions, from either side of the barrier panel, with the convertible panel being nonremovable from the barrier panel during normal usage. Also, or alternatively, a convertible panel may be provided below the work surfaces for selectively improving ventilation and air flow between the work stations.