Ipe is the editor of choice to draw figures for Computational Geometry papers and presentations. It is common to create a Ipe figure composed of other Ipe figures (stored in different .ipe files). But, there is no straightforward way to accomplish this import operation.
One way to achieve this is:
Open the source and destination Ipe figures in separate Ipe instances.
In the source Ipe instance, do a Select All to select the complete source Ipe figure. Copy it.
Switch back to the destination Ipe and Paste.