Can you have two versions of Unity installed?

Can you have two versions of Unity (2.X and 3.X) installed on the same computer at the same time? Thanks!

Sure. Install the first version, rename the install directory and then install the other version.

Make sure you do not open the same project in the two versions at the same time though. Also note that opening a 2.x project in 3.x upgrades that project to 3.x for good.

I’ve answered the same sort of question on this thread here