User Help > Working With Documents > Adding Content to a Document > To insert an open segment into a target document as a reference from the GUI
  
To insert an open segment into a target document as a reference from the GUI
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This is different from inserting a new or existing segment into a document. Here you are using the Finder window to insert an open document into another document. The target document displays after the insertion is completed.
1. Open the document that you want to insert into another document.
2. Select Document > Insert Into. The Finder window opens, allowing you to select the document into which you want to insert the open document. For more information, see Document Finder.
Document hierarchies do not need to be structured alike. For example, you can insert a test document into a requirements document.
3. Select the document you want to insert from the list of available documents by project.
4. Click OK. The open document now displays as a subsegment reference in the target document.
If you would like to view its entire contents in the Document view, select Content > Toggle Include/Insert to expand it in the current sequence.