Out of all the things that could contribute to your success, good friends top the list. But surveys show that the number of close friends people have is going down rather than up, with 1 out of every four people having no--that's zero--confidants. You don't have to be part of that statistic.

Time is the key

Anthropologist Daniel Hruschka looked at studies about what causes conflicts in friendship. The biggest complaint? A simple lack of time commitment.

But why does this hold true? Dr. Meliksah Demir, professor at Northern Arizona University, found that just doing stuff together is the component of friendship that makes us happiest. That's because sharing experiences with each other helps us feel secure and connected, and as though we hold at least a sufficient amount of importance.

When you don't give someone else your time, however, you send the message that the other individual is less than, negatively different or not worth inclusion. That message triggers a very basic fear of isolation. So people become frustrated, wanting you to reaffirm their worth. You hear this when people say, "If I really mattered to you, you'd make time."

Why we let friendships break...

Most Americans very much want friends. But we also have been taught a work-then-play mentality. We've been conditioned to believe that putting work first is responsible and a necessity for career success, and that reaching even greater success is merely a matter of putting in more hours. So because we want to feel accomplished, skilled and respected, because we want to feel like we have enough, we have trouble stopping.

And ironically, the problem only gets worse the better we do. When we quantify time through income and its value rises in a good economy, we come to see our time as more scarce, because precious things typically are rare. All our time goes to the job, because we don't want to waste. Friendships erode. And before you know it, the job is the only thing left and we're suffering loneliness at the top.

...and why we need to fight for connection

Our environment clearly makes it incredibly difficult to keep friends in the foreground, complicating what really should be basic. But research shows that being connected has a positive influence on your health, keeping you mentally and physically ready to work. And friends are amazing sounding boards for ideas, offering both encouragement and grounding through your career. So when you invest time in your friends, you're not being irresponsible at all. You're actually engaging in something that's incredibly valuable to your goals.

How to solve the problem

Because friendships are such a boon to workers, treat work and meetings with friends as dual priorities. Put time with friends on your calendar, just like you would anything else. Write. It. Down. That simple gesture will help you see time with those you care about as less negotiable. Parkinson's Law also says that work will expand so as to fill the time you allow for completion, so putting friends on your calendar in real or digital ink actually keeps work contained and efficient.

At first, you might feel odd for formalizing time with friends on your agenda. That's normal, too. You'll get over it. But if the idea truly freaks you out, there's no need to go all or none. Start, for example, with just one appointment a month or week. Then go to two. And don't forget, you don't need to meet with just one friend per appointment, either. Over time, gradually work up the number of friend appointments you have until you feel balanced and your friends are confident in you. Remember that friends vary about how much face time they like, too--the schedule doesn't have to be "Even Steven" to be fair. Experiment and find what works, and remember that shared experiences don't have to be extraordinary to have extraordinary meaning. From there, just have fun with whatever safe, legal shenanigans you and your buddies choose.