Privacy screen 78 is installed within a vertical recess 80 in shelving unit 14 and can selectively be withdrawn from recess 80 (as shown in FIGS. 11A and 11D) or retracted into recess 80 (as shown in FIGS. 11B and 11C) by a handle 82 (which may include a locking element such as a hook or clasp to retain privacy screen 78 in engagement with a coacting locking element associated with the panel wall