Parent folder path of ActiveDesignFile.

Is there some way to get the path to the parent folder. I attempted something like ActiveDesignFile.ParentFolder, but that does not work. 

If an active design file is located in a folder:

And I would like to attach a file referece from:
C:\Projects\12345\Survey\    is there some way to jump up one to parent folder.  .\ 

Path = .\Surey\  ??

Example in MSVBA Help
sFullFileName = ActiveDesignFile.Path & "\" & "Test.dgn"