Some leaders are brash show people. Others lead billion-dollar businesses despite having zero natural charisma. Some focus on the big picture. Others are more managerial. Research shows this doesn't matter. Almost any personality type you can think of can be found among great leaders. 

But are there any exceptions? Traits that a big proportion of the best leaders share? Characteristics that greatly increase your chances of climbing to the top? 

In honor of International Women's Day,​ Fortune asked 15 top female execs what personality traits they believe are key to their success. Again and again, these super accomplished women offered similar replies. If you're looking to follow in their footsteps, you might want to consider cultivating this characteristic in yourself. 

Is curiosity the key to success? 

The first quality you think of when you imagine a hard-charging executive is probably not curiosity, but again and again, the women Fortune spoke to cited a hunger for learning as their most important asset. 

"Be curious," advised IBM president and CEO Ginni Rometty. "A constant thirst to learn has served me well my entire career, especially in the tech industry." She was far from alone in mentioning her curiosity:  

  • Accenture CEO Julie Sweet called herself "a constant learner." 

  • Walmart international CEO Judith McKenna cited "curiosity" as one of her most valuable personality traits.  

  • Beth Ford, CEO of Land O'Lakes, credited "a combination of intellectual curiosity and a love of people" with her success. 

  • "Intentional listening, and the learning associated with that, has undoubtedly been key to my success," said Hershey CEO Michele Buck. 

  • Ulta Beauty CEO Mary Dillon also cited her curiosity and explained that "I told my children as they were growing up to always ask other people about themselves, to be curious to learn about others and to respect their journey." 

Science suggests these amazing women are on to something. Research shows curiosity not only helps you learn faster and boosts empathy, it also just makes you happier. Other business-focused studies show cultivating curiosity at work leads to better decisions, more communication, and smoother collaboration. Research also makes clear that by consciously changing our behavior, we can shape our personalities

So if you dream of one day joining these women on the roster of super accomplished leaders, take a minute to consider what you've done lately to cultivate your own curiosity. If you can't come up with much, it might be time to start challenging yourself to get out of your comfort zone and cultivate your hunger for knowledge.