A programmable display device selects and displays one screen data item from one of screen data groups each constituted of a plurality of screen data items indicative of control conditions. Further, the programmable display device includes a selection information forming section and a screen data group setting section. The selection information forming section is included in a project setting processing section, and based on screen data group information concerning the screen data groups, forms selection information by which one of the screen data groups is selected. The screen data group setting section is included in the project setting processing section, and sets, as a screen data group to be used, the one of the screen data groups which is selected based on the selection information.