Basic Directory addition help

[NewInstaller]

Hey all,
I am new to creating the installer, not to scripting.
However I can't seem to figure out how to add a sub directory to my nstall script with additional reference files in the subdirectory.
Under my install section I can ad flies with:
file "myfile.ext"
But what's the command for adding a directory?
I tried:
Dir
dir
directory
Directory

Nothing seems to be working.
Thanks for any ideas.