Yes they do. Usually a first class honors (with a paper published) for your undergrad is the first prerequisite.

The second prerequisite will be the ability to find a supervisor who's willing to take you on with the topic that you wish to do.

This post has been edited by malleus: Jan 11 2012, 12:13 PM

I don't think something like a PhD is practical to be done on a part time basis. its just that intensive.

And you'll be put to work too. Doing all the stuff that your supervisor don't want to do. Like handling 1st year students, marking exam papers, assisting in research and so forth. You'll be paid lar.. but this means if you're thinking of work outside of the university, not very like as you just won't have the time to handle it.