When to introduce a girlfriend to your parents ?

I’ve been wondering lately, when is the right time for a guy to introduce his girlfriend to his parents? Should he do it with all the girlfriends or not? Should there be special requirements so that the girl meets the parents? Should the relationship has to have lasted a certain period of time at least to make the presentations? What does it mean if the boy doesn’t make that step? Does it mean that it’s not that serious? That he’s planning to dump her a day or another? That’s he’s waiting for a better moment and if so, what is the right moment?
Is it that important for the boy to introduce the girl to the family? Is it important for the girl? Does it have to mean something special? Can’t that happen event there’s no engagement party planned by the couple? Too many questions…and hardly any answer…

There’s a good friend of mine who’s been dating a guy for some weeks now but it’s still a beginning of the relationship…there are great together, they get on well, there’s attraction and feelings and it’s a rather cool relationship that they have…they don’t see each other every single day, but they talk on the phone at least once a day…he has introduced to her to his closest friends very quickly…it should mean that he’s happy to have her, proud of her right…she hasn’t found the time to introduce him to her friends because it’s something that should be planned a bit earlier, while with his friends it just comes when it comes…and she loves to enjoy the moment they have just for the two of them, which is absolutely normal…so the couple is fine, is happy and that’s great…

He got the visit of his parents and relatives for a week and she couldn’t see during all that time…she perfectly understood that he wasn’t ready to introduce her to them…maybe because the whole thing is new…and she just have been waiting patiently the moment she’d be able to see him and hold him and hug him and kiss him and feel his body against her again, feel his breath, feel so well in his arms…
And though she understood all that, she just couldn’t help herself wondering when is the right time…what makes a boy feel it’s the right time…and meeting the parents, does it have to mean something serious?

So you tell me now guys? What do you think?