Once you have said, "Leave me alone" and they continue to bother you I consider that stalking. Espciall if you notice them showing up places that you wouldn't commonly run into them at, or they appear to just be anywhere you are.

My anti-stalking device:

Legally, if there are three instances where you have made it clear you do not want their attention, and they pursue you anyway, that's stalking.

You have to make it abundantly clear the first time that you do not welcome their attentions. If you have done that, and they persist, after the third time, you can actually file an injunction against them. You will need to keep a written record of all the instances, and have at least one reliable witness to each one. If you don't have a witness, and he is there, call the police and let them witness his presence.

If they are making unwelcome phone calls, showing up unexpectedly at your house or anywhere else you are, or sending you unsolicited gifts when you have told them to stop, that's stalking.

I had an ex once who ran an apartment complex where my best friend lived. Every time I went to see her, he would show up there, fiddling around in the hall pretending to do something. When I left, he was always in the parking lot, saying he wanted to make sure I got to my car o.k. I asked the police if it was harrassment, and he said it was stalking, and gave him a warning.

If you fart in front of them and they don't leave, they're not stalking you.

If you feel physically threatened by their actions, don't waste any time. Call the authorities NOW. There can be a fine line between stalking and "very interested." If you've told the person you don't want their company, it could just be that they are trying to break down your resistance. But if they don't have enough sense to leave you alone when you tell them to, or drop by unexpectedly way too often for your comfort, I'd let them know they are making you uncomfortable and that you will take measures to make them stop bothering you. If this person truly wants to build a healthy relationship with you they'll give you some space and time to think about the possibility instead of scaring you by being too pushy.

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Here's what to do and say when you're just not that into her. ... If anyone asks, just tell them "It didn't work out." When someone tells you she has a hot new ... Stalking - or instilling fear into a reasonable person without outside
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I think that legal action should be taken when every where you turn that someone is there watching you, or constantly trying to talk to you and you have already said no !! Pressing charges can be a very tricky thing without a witness. So if someone is following you and you are very uncomfortatable with their presents I would contact the police right away. People that are obessed with other people can be very scary. Be careful and good luck.

If you are in a relationship the two of you should have an understanding of when and where to contact each other. If you have already told that someone that you are not interested and they continue to be everywhere you are then it is stalking without a doubt and contacting the police is the right thing to do.

http://www.flickr.com/photos/karenebiggs/3396535133/

As a rule. If you cannot tell the difference, it's stalking

Key word here is relationship. True stalking is beyond any relationship.
Are both sides of a relationship able to tell the other about feelings, hopes, aspirations? Can he/she talk about her family, homelife, upbringing?
If any of these appear to be phony or cannot be verified, then a relationship cannot continue. Relationships are built on trust.