If you have a lot of professional experience and high marks on the GMAT you’ll be able to get into a surprising number of MBA programs at prestigious universities. I’m sure networking also helps.

There are plenty of MBA programs in the UK that don't require an undergraduate degree. A person in my family got onto one with no real 'high school' level qualifications even! He struggled and dropped out. What they really want from you is fees.

Sorry for the delay, accidentally set my anti-procrastination timeout to 5 hours.

I articulated through a Graduate Certificate program that encompassed 4 of the compulsory subjects for the 16 subject MBA. I had to obtain a credit average to move into the MBA itself.

Australian universities recognise prior work experience for a MBA. If you've working been in a business related field (virtually most office jobs) and have some aptitude there's a good chance of getting admitted.