An introduction line that is. Do you ever get invitations from people with whom you have no apparent connection? Of course, meeting new people is one of the best parts of any social networking site. However, too many LinkedIn requests remain unaccepted because people don’t know – or remember – the sender.

Unless it’s someone you talk to regularly (the co-worker who sits next to you, a close friend, your sister), I highly recommend writing something in addition to the automatic “I’d like to add you as a LinkedIn connection.” For example, let’s say you want to send an invitation to:

A colleague you worked with 10 years ago: They may remember you, but there’s no harm in a reminder. You can say, “I’m not sure if you remember me, but we worked together at XYZ company. We were both in the ABC department.” Re-introducing yourself can be the first step toward building a relationship with someone who previously was only an acquaintance.

A classmate from high school: If you weren’t close, you can use the same approach as above. If you knew each other well, something as straightforward as “It’s been a long time! We haven’t seen each other since high school,” is likely all you need.

A person who works for your dream employer: This is where it’s most important for you to include an individual message. Mention how you came across their profile (a keyword search, members of the same group, recommended by a friend, etc.) and why you’re contacting them. If you’re looking to establish connections at a company, one option is, “I came across your profile when looking for professionals who are employed by XYZ company. I’m hoping to learn more about what it’s like to work there – would you be open to a brief telephone informational interview?”

Since LinkedIn exists to establish and re-establish professional relationships, you could be missing out on opportunities if you don’t include a customized message. The above suggestions should give you an idea of how to address people in an invitation, but use your judgment. The key is to write something personal, and each note should be crafted on a case-by-case basis.