The following command in a group will give you the button.
<button idMso="StylesManageStyles" visible="true" size="large"/>

Hi Charles

Think I am there now. Did a lot of research based on what you taught me and now use the following in the procedure.

Application.Dialogs(wdDialogStyleManagement).Displ ay

The style dialog I was using I suspect was from an addin called FSPro. It is a variation on the standard Word one above. The one above does all the same things, but not in such a visually appealing format. That had me confused for a long time.

Anyway, the journey taught me a lot about ribbons so thank you for that. Hopefully my new ribbon will do all I want.