Simplest method is:

Dim a As String
a = "c:\windows\system32\xcopy c:\wf.exe c:\aa.exe "
Shell (a)

BTW, FWIW, I would rather use the filesystemobject to do file manipulation
like copying, deleting and renaming files than shell system commands.

On Mon, 4 Apr 2005 13:06:56 +0530, "Abhishek"
<abhi_narulkar@rediffmail.com> wrote in
microsoft.public.word.vba.general:

By invoking your shell with the appropriate arguments.

Assuming that it's the command COPY of CMD.EXE you desire to execute,
the command might look like:
 Shell ("cmd /c copy source.dat target.dat")
For details see CMD /? from a CMD prompt.

However, as Vince suggested, methods native to VBA are probably
preferrable.