It’s widely believed that the most successful romantic relationships started out as friendships. In fact, according to a recent survey, 40 percent of the 2,373 18-to-34-year-old respondents said they started as “platonic friends” before getting romantic.

But taking the leap from the friend-zone to the love-zone can be risky when you don’t know if your pal wants to be more than friends, or if a romantic relationship will even work out.

The question to consider is this: Why haven’t you taken your friendship to the next level by now? “If you and your friend have a good connection and mutual respect, it may be worth taking the relationship further to assess your romantic chemistry," says Andrea Syrtash,author of “It's Okay to Sleep With Him on the First Date: And Every Other Rule of Dating, Debunked." "You already have many ingredients that lead to successful romantic relationships.”

What’s even better is if you know both your values and goals align.

“Knowing someone’s history, their friends, lifestyle and even their mood swings ahead of time are all helpful benefits to being friends with someone first,” says research psychologist Dr. Frieda Birnbaum.

Of course, the reality can be different. Crossing the line with any good friend risks losing that friend altogether. But if you’re already thinking about your friend in a romantic way, the dynamic of the friendship has changed, so you may as well test the waters.

Start with your inner voice, says marriage and family therapist Dr. Karen Ruskin.“If in your gut you feel the person brings you in and pushes you away, often that’s a sign they are not thinking you are right for them, but they don’t want to lose what they like about having you around.”

If you can’t seem to gauge their signals, it's possible that your friend may not know how or where to take the relationship himself or herself.

Birnbaum says you should begin by asking something simple, like, “Did you ever think of us dating?” or saying, “We have so much in common and like the same things that it seems we have more going than a lot of the people I date.”

Also, it's helpful to show action through how you feel. This doesn’t mean throwing yourself at the other person, but making simple gestures, like increased flirting, or suggesting you meet at a laid-back romantic wine bar instead of the rowdy sports bar you usually frequent. Then, see how he/she reacts.

Don't be afraid to make the first move, either. Besides, if you're waiting around for the other person, you may have to hide your feelings forever.

"Being vulnerable and taking risks is an integral part of love," says Syrtash. "In this case, the potential reward may be worth the risk.”

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