You can get a good case of whiplash reading advice about how effective CEOs are supposed to do their jobs.

They have to be great ground-level managers—but strategic visionaries too. They have to have a head for numbers—but not get stuck in the weeds. They have to be hard-headed get-‘er-done types who are immune to others’ emotional reactions—but possess deep reservoirs of emotional intelligence. (Whenever somebody mentions these contradictory demands, I can’t help but think of a Simpsons scene in which a cranky woman impossibly insists that a supermarket bag boy put all her groceries in one bag—but that the bag not be heavy.)

“Part of [my responsibility] was recognizing where everybody was emotionally, Thompson said.

So it’s some trick to be good at both, but it may be that the best CEOs have a knack for it. A new study by executive search firm Russell Reynolds Associates took a close look at what differentiates CEOs from other types of leaders. Their survey of more than 3,700 people, including 134 CEOs, revealed nine overall traits that distinguish CEOs, broken down into three general categories: forward-thinking, intrepid, and team-building. Interestingly most of the traits the survey identified as distinguishing top leaders involve balancing acts:

• “Is biased toward action but not too impulsive”
• “Is thick-skinned and perseverant but not insensitive”
• “Seeks to understand different perspectives but does not overanalyze”
• “Displays intensity/emotion but maintains control”

“These paradoxes suggest that CEOs possess a broad range of capabilities and—more important—know when to ‘flex’ one opposing capability over another to achieve the right outcome,” write the study’s authors.

There’s nothing quite like a crisis to help surface some of these skills, something I learned while talking with Tracy L. Thompson, executive director of the New England Law Library Consortium for an article in the latest issue of Associations Now.  NELLCO was in the unfortunate position of having its board meeting timed around the Boston Marathon bombing last April, but Thompson stood firm on holding the meeting’s first day shortly after the tragedy. A citywide manhunt made their venue inaccessible the next day, however. “My first thought was, ‘How am I going to get everybody together? Where are we going to relocate to?'” Thompson told me. “But I quickly realized that wasn’t going to be possible.”

Holding a critical board meeting on the first day, as I see it, qualifies as standing firm. (It wasn’t a universally popular decision.). Trying to force a board meeting on the second day, however, could only be stubborn, insensitive, and lead to stronger pushback. (Consdier that Simpsons bag boy—pushed to his limit, he called a sit-down strike.) Thompson understood the reactions that were appropriate for her board in the particular circumstances it was in. “Part of [my responsibility] was recognizing where everybody was emotionally,” she said.

Thompson credits her board for stepping up in a challenging moment, but I’d also credit Thompson herself for displaying the kind of flexibility that allowed those around her to do their best work. Flexibility is hard to measure and hard to train for, but it’s one of those important soft skills that CEOs and those in the pipeline ought to train for.  The Russell Reynolds Associates survey authors recommend drafting individual development plans for their leaders, and another recent study from the Bridgespan Group emphasized the need to create stretch assignments for those with CEO potential. “Be flexible” sounds like a no-brainer, but it doesn’t happen by accident.

What have you done in your own organizations to help cultivate a skill at balancing conflicting needs? Speak out in the comments.

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