Have Service Inherit Environment Variables from Command Prompt Window

Hello everyone.

I am attempting start a service and have it respect environment variable
changes that I have made in the current Command Prompt window's environment.
Basically, I want to do this...

C:\> set FOO=BAR
C:\> net start MYSERVICE

....and have MYSERVICE see FOO=BAR in its environment variables.

I used Process Explorer to examine the Properties of the MYSERVICE service
and found that its environment variables did not include my (modified) FOO
environment variable.

How might this be accomplished?