Are you struggling to balance competing priorities and deadlines? Here's an exercise that may help: Ask yourself how much you'll care about a task or issue when you're 95.

At GrowCo last week, I had the great experience of hearing a talk by Marshall Goldsmith called "The Delusion of Success." The whole session was thought-provoking, but one of the most thought-provoking moments was when he asked the audience to imagine ourselves at 95, on our deathbeds. "Before you draw your last breath," he said, "you look back over your life." (If you're reading this and you're already in your 90s, make it 105. Or 115.)

What would you see? What do you care deeply about today that 95-year-old you would consider insignificant? Are there things 95-year-old you would wish you'd spent more time on? Most importantly, what changes should you make today so that when 95-year-old you takes a good look in the rear-view mirror, he or she will be happy with how you spent your life?

The answers will be different for different people. But it's a useful exercise for everyone because trying to imagine what will really count when you have your whole life to look back on might help you make better decisions right now. Here are some important ways that we may all see things differently at 95 from the way we do today:

1. 95-year-old you will care less than you do about your job.

It's pretty much a certainty that 95-year-old you won't look back and decide that you had a good life because you never missed deadlines. Or because you hit the revenue numbers you wanted. He or she may care that you built a successful company, or maybe not. Bronnie Ware, a Hospice nurse who worked with the dying for eight years reports that every male patient she worked with expressed regret over working too hard. Besides, working too hard is bad for you in many, many ways--here are just 10 of them.

I understand that working less hard is a tough prescription to live up to, especially in our work-obsessed culture and most especially if you're an entrepreneur. And I'm writing this column at 9 o'clock on a Sunday night myself. But the fact remains that all of us, myself included, need to find the time to have rich, fulfilling, relationship-filled lives outside our work, even if we find that work rich and fulfilling as well. (Here are 8 reasons you may owe someone in your life an apology for spending too much time at work.)

2. 95-year-old you may wish you spent more time with your family.

This is the subtext to "I wish I hadn't worked so hard," because most of us, whether business owners or ambitious executives, struggle with the fact that we spend a lot of time working when our loved ones would really rather have us around. And while we may enjoy our work, we regret not having that time to spend doing things--or doing nothing--with the people we love most.

But time flies by and children grow up fast, and spouses grow older or grow apart, and those relationships can be permanently changed or gone altogether before we know it. I don't know what the answer is to this conundrum, I just know it's important for all of us busy professionals to find it.

3. 95-year-old you may wish you'd built stronger friendships.

That was another common regret that Ware noted: "I wish I had stayed in touch with my friends." All of us have friends, from childhood, from past jobs or past lives, whom we love but never see. My most longtime friend has known me since I was 11, a historian of my life who would be impossible to replace. Many others have been my friends for 20 years or more. Keeping in touch with people who are scattered around the country or the world, and have busy careers of their own, is never easy. But it's still worth doing.

4. 95-year-old you will want to know that you helped others.

When your top priority is driving your company forward, or climbing the ladder within your organization, helping others can get left behind. But if you let that happen, your older self may be sorry, Goldsmith says.

Helping people can take many forms: contributing to charities--or starting one of your own--helping out a friend of acquaintance in need, mentoring less experienced executives or entrepreneurs, volunteering, using your platform to get the word out to others about a situation where assistance is needed. You can do any or ideally all of these. (Here are ways some clever businesses combine giving with social media promotion to engage with customers and help those in need at the same time.) At 95, you'll want to know that you're leaving the world at least a little better than you found it.

5. 95-year-old you will want to know you did work that mattered.

Many of us struggle mightily with the question of whether the work to which we devote most of our waking hours goes beyond delighting customers and creating a healthy revenue stream. It should be something we love. And it should have meaning that goes beyond just business success.

How do you create that meaning? The answer is different for everyone. But if you've never done this mental exercise, try it now: Imagine what you will think of your entire career looking back on it from many years in the future. Envision your own obituary, and what you would like it to say. And then--this is the hardest part--start living the life that will get you there.