Wait if application open

I am trying to run two auto macros (in different files) one after the other where the run times are unknown. Both macros conclude with "application.quit" I need a function which will allow the second macro start immediately after the first has closed Excel. Is there any means in vba of determining if excel is already open when starting the second file ? Something like "wait if application already open" ?

Any ideas welcome!

Thanks
Astrikor