The gating hierarchy shows the gates drawn and applied to determine the populations selected in the "Populations" dimension box. This is often useful for answering questions such as "How did you identify your Treg cells?" Choose a representative file using the select box and draw out the gating hierarchy for your population(s) of interest.

If the Gating Hierarchy panel is closed, click on the little right arrow to the left of "Gating Hierarchy" to make it point down; that will open the Gating Hierarchy panel.

To move the percentage labels shown in the plots, go to the gating applet by clicking on "Edit" in the "Populations" dimension box, select the gate you want to edit from the gate list, and move the little box with the flag elsewhere in the gating plot.

To change the file, select a new file from the drop-down menu and click on "Show Hierarchy".

If the hierarchy doesn't look right, go to the gating applet and check "Manage Populations".