Abstract: An index tab system for useful organization of articles in objects such as hanging folders, file folders, expandable folders, index cards, index dividers, notebooks, binders, and the like. The index tab system provides a plurality of index tab forming structures that can be affixed to any of the above mentioned objects for indexing the articles or the contents therein. The plurality of index tab forming structures includes interlocking structures for selective formation of tab cavities and selective placement of the tab members along the object.