This would very much depend on the situation. Usually, people who make a specific effort to introduce themselves have something to gain from meeting you. It could be that this woman is attracted to you, especially if there is no other reason for her to approach you. However, there could be something else she wants from you: she might be interested in your friend, you might be useful to know at work, one of her friends might be attracted to you ... and so on. All things considered, her wanting to meet you is a very positive start, so if you are attracted to her, stay aware and watch out for further signs that she likes you.