To be a great manager you need to listen to your people, develop predictable policies that unleash their potential, and fight for your team when things get rough. But to be a great leader you need a whole other X factor - you need to be inspirational.

While great managers smooth the path, great leaders imagine the end goal it leads to and inspire others to work to get there. Managers hammer out the details, leaders set the vision.

That means that while it's relatively straightforward to learn how to be a good manager (Google has a whole suite of free tools to help, if you're interested), learning to be a truly inspirational leader seems more daunting. How do you teach imagination, charisma, far sightedness, and force of will?

New research from Bain & Company suggests a good place to start. As partner Eric Garton explained recently on HBR, the consultancy surveyed 2,000 Bain employees from all levels of the organization to find out what made a leader truly inspirational. Analysis of their answers yielded 33 possible traits that help make a leader inspiring, but one characteristic stood out as the most important by far.

The trait that matters most for inspirational leadership

Garton kicks off his post by busting common stereotypes about inspirational leaders. They're not all extroverts, charismatic showmen, or Jobsian prophets on a mission to change the world. "We found that people who inspire are incredibly diverse," writes Garton. "There is no universal archetype." 

But despite these many differences, the research did uncover one essential similarity shared by all inspirational leaders. "Although we found that many different attributes help leaders inspire people, we also found that you need only one of them to double your chances of being an inspirational leader,"Garton reveals.

What is this trait that matters more than any other? Centeredness. "This is a state of mindfulness that enables leaders to remain calm under stress, empathize, listen deeply, and remain present," explains Garton. 

Centeredness is "a mandatory skill," Bain writes of the survey results elsewhere. "Just as leaders need to be able to meet their performance objectives to be rated as satisfactory, for example, we recognize that leaders need to be able to stay centered to inspire. Being centered is a precondition to using one's leadership strengths effectively."

That means whatever else you excel at - whether it's energizing others, setting the tone, or focusing in a chaotic world - you won't be able to utilize that skill if you can't stay calm and centered when the pressure is on.  

How to become more centered  

With centeredness so important for truly inspirational leadership, it's no shock that so many executives and entrepreneurs are turning to meditation, a leading way to train yourself to stay centered no matter what whirlwind surrounds you. This isn't woo-woo spirituality. Science shows that meditation causes measurable changes in the brain that short circuit panic and speed learning.

And if you're not the sitting-on-a-pillow-chanting type, no worries. Mindfulness training comes in a vast array of flavors that can work with basically any personality or lifestyle. Some experts even suggest that you can get a boost in centeredness simply by engaging in any sort of activity, from gourmet cooking to rock climbing, that demands you retain laser-like focus on the present moment. Bain offers a simple exercise to get you started (along with a deep dive into the brain science of centeredness).

Whichever pathway to greater centeredness you choose, the results of this latest Bain research are clear: if you want to inspire, it's a trait you're going to have to develop.