You know the feeling: you meet someone new—at an event, a party, or at work—and you just “click.” You immediately feel comfortable and sense that you can just be yourself around this person. These connections feel magical, but what's the science behind them? Why do we click in with some people in some situations but not in others? And how does clicking with someone transform the nature of our relationship?

In their new book, Click: The Magic of Instant Connections, brothers Ori Brafman and Rom Brafman (who co-authored Sway in 2008) explore what makes people click. Longitudinal studies indicate that romantic couples who immediately click (as opposed to connecting more gradually) are significantly more likely to exhibit passion in their relationship years later.  And it's not just about romance: professional teams that click together are more productive and more engaged in their work than their counterparts.

What makes us click with others? The Brafmans reveal five “accelerators" that promote clicking:

1.  Vulnerability: The more we share and make ourselves vulnerable, the easier it is for others to see the person behind the mask and to connect with us. When you feel touched or hurt, speak up. The more you let people in, the more they'll reciprocate, so open up and disclose your feelings.

2. Proximity: The physically closer that you are to someone, the more likely that you will connect with them. What's surprising is just how much the last few feet matter. For example, university students who were randomly assigned to centrally located dorms reported having more friends than the ones who lived in end units. Showing up to a meeting in person means getting to participate in pre-meeting talk that fosters genuine connection (for example, “Let me tell you about what happened to me this weekend”). You miss out on these types of contacts with audio and video conferences.

3. Similarity: Similarity is the initial glue that prompts us to become more familiar with one another, and even the small stuff counts—for example, being born in the same year, being a fan of the same sports team, having the same taste in music, or sharing a favorite vacation spot. Therefore, when similarities come up, make sure you take advantage of them. The quality of the similarities isn’t the most important factor; it’s quantity that really matters.

4. Attentiveness: When people really “show up” and they're in the “zone” so to speak, people naturally connect with them.  Moreover, people who are attentive make others around them attentive too—and much more likely to click.  Whether you're doing a pitch for investors or participating in a meeting, pay careful attention to what's going on and look for opportunities to engage others.

5. Clearly defined community and shared adversity: Going through a tough experience together—completing a challenging work project, going through breakups at the same time—makes us feel like we’re part of the same community or group. And the more that connection is framed as being its own little world—war vets, support groups, freshman dorm mates—the more powerful the connection becomes.

Whether in your business or personal life, if you need to “click” more often, you should read Ori and Rom’s book. No pun intended, but “click here” to buy it. It may be just the thing to help you develop powerful new relationships.