The busy outnumber the productive by a wide margin, caught up in a never-ending flurry of meetings, phone calls, email, brainstorming sessions, “management” and other treadmilling. At the end of the work day, a Cold War ensues between the managers and their employees about who will leave the office first.

If you can relate to this scenario (I know I can), and feel your life force being drained from you by spending endless hours furthering other people’s business objectives, then ask yourself this: What if you could get the same amount of work done in 7–8 hours as you currently do in 10–12 hours? In fact, if you could get the same or more value from your work in less time, wouldn’t it be crazy not to?

If you’re feeling weighed down by overwork, losing touch with those who matter, losing touch with yourself, then try the Five O’Clock Challenge. The challenge is incredibly simple: Leave the office every day at 5:00 PM.

Give yourself a no-overtime policy: No pagers, no mobile phones, no work-related email, no “one last thing to finish” after 5:00 PM. When the time comes, logout and leave. This challenge is applicable whether you’re self-employed or working for The Man, whether you work in a cubicle farm or in your boxers on the couch.

The goal of this challenge is to amplify the value of your time by setting boundaries on your availability. By forcing yourself to work “only” eight hours a day, you:

Focus on only what needs to be done. Time constraints force productive choices, rev up your concentration, and encourage you to find creative ways to do more with less. You also become keenly aware of what is really adding value to the product, and what’s just keeping you busy.

Time constraints force productive choices, rev up your concentration, and encourage you to find creative ways to do more with less. You also become keenly aware of what is really adding value to the product, and what’s just keeping you busy. Encourage others to respect your time. By regularly staying at the office late, and coming in on weekends, you’re conveying that you don’t value your time. When it’s clear that you’re available only until 5:00 PM, your boss will think twice about calling you into a meeting.

By regularly staying at the office late, and coming in on weekends, you’re conveying that you don’t value your time. When it’s clear that you’re available only until 5:00 PM, your boss will think twice about calling you into a meeting. Have more time for other experiences. Less time spent furthering other people’s goals means more time to further your own, start your own company, meet girls, write a book, learn to speak another language, or become a world record-breaking Tango dancer.

Less time spent furthering other people’s goals means more time to further your own, start your own company, meet girls, write a book, learn to speak another language, or become a world record-breaking Tango dancer. Improve your health. Reclaiming your precious time to spend more of it outside the office is a healthy choice, physically and mentally.

Reclaiming your precious time to spend more of it outside the office is a healthy choice, physically and mentally. Make more money. Working fewer hours for the same salary means an automatic raise.

I applied this principle to my own life on a recent contract with a high-profile tech company. I made sure from the start that my contract included the minimum number of hours I was required to work — 35. Despite a corporate culture of “constantly overburdened” developers, I opted out. I studiously logged my seven hours per day, five days per week, and made a healthy six-figure salary, and almost certainly put in far fewer hours than anyone else in the company.

If you feel anxious about telling your boss that you’re going home on time today, then take it slowly. Start by leaving on time just one day this week. Then a couple days next week. See how your boss reacts. You might have some interesting realizations about whether you belong with this company.

Working less isn’t about laziness or slacking. It’s about valuing your time, learning to truly make the most of it, and becoming acutely aware of how much time you spend furthering other people’s goals.