How to toggle between vim buffer and command shell screen in vim?

Starting gvim opens a new window, so the terminal window stays available for commands. For intermediate "shell escapes" I do :sh to get access to a shell session, and type <Ctrl>-D to exit it; no fg is needed, but a prompt is added in this case to the console shell. And with no X running I start two consoles, one where vim is running, and the other where the shell is running, and I switch consoles by (in my case) e.g. <Ctrl>-<Alt>-<F1>. (Depending on the actual needs, one of those options should fit; I hope.)