Best way to run physical MacOs installs?

[AlexAlexAlex]

I have a number of older installs of MacOs on external HDs (copied from my computer with CCC). I am looking for the absolute best way to run those from within my main MacOS desktop. I understand it's not possible to run physical drives, so what is the best way? Thank you

 

[OakesG]

Yes, OS X can be run in a virtualized environment but the license of OS X client prohibits this use. OS X Server can legally be run in a virtualized environment but only on a Mac OS X host (not under VMWare on Windows, sorry). We use a VMWare Fusion image running OS X 10.5 Server for testing deployments.