Running OSX from Bootcamp It's well known that to run Windows on a Mac you can either use a virtual machine install or reboot into a Boot Camp partition.  You can also, with suitable software like Parallels Desktop or VMWare Fusion, open your bootcamp partition whilst booted into OS X.

Is it possible to do this the other way around?  If I boot into Windows via Bootcamp, can I start my OS X partition via virtual Machine software?
I am afraid not, it's not possible to virtualise Mac OS X in order to allow it to run within Windows, at least not by effectively opening up your genuine OS partition and running is as though it was a virtual machine, which can be done for a Windows Partition within OS X.

It is possible to run Mac OS X in a virtual machine from a Windows OS, but it is not officially supported by any of the major vendors, and requires a lot of messing around.  Even if you did this, you would not have the ability to genuinely boot straight into that instance of Mac OS X, as it would only be available as the virtual machine.

If you need to access both simultaeniously, you need to stick to booting to Mac OS X, and then opening the Windows partition as a VM.