6 Invaluable Lessons My Clients Taught Me in 2015 Their wisdom won't just shape how you work, it will shape how you live.

It's hard to believe that 2015 is almost over. I had so many incredible opportunities to help companies large and small build more "bankable" leaders and therefore more bankable businesses. As is always the case, my clients taught me some powerful lessons that haven't just informed how I work: Some have actually shaped how I live.

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When I codified last year's learnings, I got such a positive response that I thought I'd make this an annual thing. So, read on!

1. Put your money where your mouth is.

Of late, my consulting practice has focused on larger, longer-term projects. The reason is simple: I want to help my clients make a tangible impact on their business. If a company needs to grow its leadership capability, for example,coaching one manager may be helpful, but to see dramatic returns, the company needs to invest in leaders across the board.

This is true for any strategic investment. In the early 2000s, Blockbuster committed only partially to funding Blockbuster Online despite the belief that this vertical would help the company remain viable. Had Blockbuster gone "all in," however, it might have averted bankruptcy.

Along these lines, something I hear from potential clients is, "It's a bad time to invest in our leaders, because [our business is struggling, we're really busy, etc.]."

But much like having children or going on vacation, there's never "a good time." I'm not suggesting blindly spending money just because something is important (as Mark Zuckerberg learned when he invested $100 million in the Newark Public Schools). But, if a solution to a big problem has a powerful ROI, I've seen my smartest clients reap the rewards by putting their money where mouths are.

2. Safety matters, now more than ever.

You've probably heard of Maslow's Hierarchy of Needs. The hierarchy argues that we must have our basic human needs (like sustenance and safety) met before even thinking about needs like belonging, achievement or meaning. This year's attacks in Paris, the United States, Lebanon, Kenya and elsewhere have fueled our fear to seemingly unprecedented levels. And, if we don't feel safe, we find it hard to focus on much else.

For leaders, the term "safety" as applied to the workplace carries an even broader definition. One manager I know said it perfectly: "My responsibility doesn't end with physical safety -- I also have to make sure my team feels psychologically safe." And that means reducing anxiety through clear expectations, job security and a trusting environment.

3. Humble leaders beat arrogant leaders every time.

In recent years, research has shown that, individually and collectively, we are becoming more narcissistic -- and I'm not just talking about millennials. Though only 6 percent of the population is diagnosable, powerful societal influences are tempting the rest of us to join the cult of self. For instance, one study randomly assigned participants to one of two groups: One group's members spent time on their social media pages, and the other group simply surfed the Internet. The social media group showed immediate increases in narcissism!

Not surprisingly, narcissism hurts organizational performance. Self-aggrandizing CEOs, for example, tend to make riskier investments, and their organizations tend to exhibit an extreme and volatile performance. Our society's trend towards narcissism presents a challenge for leaders to fight the cult of self at all costs.

My most successful clients understand their limitations, listen to others and don't have to be the smartest person in the room. Balancing humility and confidence is essential -- not just to succeed at work, but to sustain our relationships with our families and friends.

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4. Self-awareness isn't our default state, but choosing to get there is worth the effort.

Self-awareness means understanding yourself and how others see you. As I've argued before, self-awareness is also the meta-skill of the 21st century: Among other benefits, self-aware people are happier with their careers and relationships, are better students, perform better at work and run more profitable companies.

Unfortunately, self-awareness rarely comes naturally. We are generally motivated to see ourselves in a positive light, even if that view is inconsistent with reality. And even when we want to know the truth, we often can't see it. For example, one recent study showed that almost 60 percent of people surveyed said they wanted to change jobs, but of that number, almost half didn't know what their next chapter should be!

Currently, I'm studying people who have made dramatic improvements in their self-awareness -- our "special unicorns" as our team affectionately calls them. They describe self-awareness as more of a state than a trait -- something we can prioritize and hone throughout our lives.

Carl Sagan once observed, "It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring." My most esteemed clients regularly make the brave choice to grasp the universe, and themselves, as they really are.

5. Other people's opinions about us are more important than we realize.

I was recently talking to a friend who wanted to change the direction of his business but didn't know where to take it. The advice I gave him wasn't what he expected. "Trying to find the answer within yourself probably won't help much," I observed. "In fact, introspection has a surprisingly limited value in building self-knowledge."

Instead, I suggested he ask the people who knew him best what they thought he could do to play his passions. Then he should compare their feedback to his self-observations and see if he gained any new insight.

When it comes to our skills, passions and patterns, we can sometimes be the last to know. But are our self-views totally worthless? Of course not. True self-awareness is a complex interweaving of both our views and others' views of us. The problem is that most people prefer to ponder their own perspective.

My clients who regularly seek feedback (and really listen to it) have far more control over their destiny than those who don't. After hearing the results of her 360 leadership degree assessment, one client recently observed, "I hate doing stuff like this -- but it's the bad news that's good to hear." Truer words were never spoken, and it's not a coincidence that she is a highly successful leader.

6. Remember what matters the most.

For many of us, alongside the joy of engagements, marriages and the birth of children and grandchildren, 2015 has brought death, divorce and illness. In spite of those life events, quite often we still prioritize work -- oftentimes far too much, given the circumstances.

Earlier this year, a family member was nearing the end of a heartbreaking battle with cancer. One day at the hospital, I took a client call. I dialed in, but within the first minute started to tear up -- it was mortifying. I was surprised when, with equal parts forgiveness and firmness, my client ordered: "Get off the phone. We can reschedule. At the end of the day, this call doesn't matter."

His words were a poignant reminder: The money, significance and meaning we get from work really don't matter when the real issue concerns our loved ones and our health.

Melinda Gates, whose job quite literally entails saving the world, said it well: "On the day I die, I want people to think that I was a great mom and a great family member and a great friend. I care more about that than I care about anything else." That really puts things in perspective, doesn't it?

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