Some friends seem built-in: they came into your life at a young age or were introduced to you through family. When it comes to pursuing a friendship, however, or deciding whether or not to let someone become your friend, there are some important qualities you should look for.

Look for Loyalty

A friend who sticks by you through thick and thin is one to keep by your side. If you have a friend who proves commitment to the friendship, don't let that person go. A loyal comrade will stick around no matter what troubles you go through -- together or alone. “Why Loyalty Matters” authors Timothy Keiningham and Lerzan Aksoy illustrate what loyal friends are with a party scenario: Many friends will come to the party, but loyal friends will help you clean up when it’s over. They will always be there when you need them.

Treasure the Trustworthy

Because trust strengthens the bond between friends, close pals should be trustworthy confidants. According to “Why Loyalty Matters,” one-quarter of Americans do not have a close friend they can trust with their secrets. Keiningham and Aksoy also report that in 1985 the average number of confidants per American was three as compared to today’s average of two.

Grab a Good, Empathetic Listener

Good friends should be not only trustworthy but also avid listeners. When you’re venting about how bad your day was, the best response from your friend would be empathy. According to a 2013 study by the University of Virginia, humans require friends they feel are on their side. James Coan, psychology professor behind the study, found that a person’s self-identity is reflected in those who empathize. He adds that close friends are so important that they almost become a part of you, which increases increases your ability to empathize with each other.

Have Fun With a Funny Friend

If you’re going to spend a good deal of time with someone, you probably want that time to be fun. People generally choose the company of those they find enjoyable and amusing. Sharing a laugh with someone is a way to bond and feel closer. According to “The Science of Laughter” by Robert Provine, published by “Psychology Today,” laughter not only brings people together but also proves beneficial to your health. Find a humorous friend and you’ll find that your stress levels decrease!