Emily Levine has worked with a fair share of successful people.

Levine is the executive vice president at recruitment firm the Career Group Companies. In her more than 14 years working at the firm, "I really homed in on a niche of working with private family offices, ultra-high net worth individuals, celebrities, athletes, musicians," she says.

Among her clients are the Kardashian-Jenner family, Kevin Costner, TV anchor Maria Shriver and others. She helps them fill all sorts of roles: "chief of staff, personal assistants, estate manager staff," nannies, personal chefs, etc. Most roles pay six figures.

Though the types of roles they're hiring for vary, Levine says there are three traits that many of her successful clients always look for in an employee.

Problem solving

The first is the ability to solve problems.

"If they're a singer or they're practicing on the court if they're in the NBA," Levine says of her clients, "they need someone who's going to handle everything from the minutia all the way up to providing support for those bigger issues that they're facing."

Depending on the person she's recruiting for, they might need help organizing their calendar or they might need help moving their business forward. Whatever the problem, they ultimately want someone "who's going to provide solutions and improve their efficiency throughout the day."

Flexibility

Many of Levine's clients have erratic schedules.

"Most executives, athletes, musicians, have really intense schedules," says Levine, "and it's not typical for them to be confined to a nine to five." As such, they expect the people who work for them to be available throughout the day as well.

"Most of these jobs that I'm placing require flexibility to work nights and weekends," she says. A lot of her clients travel internationally as well, "so they're on different time zones, so the people supporting them on [their] team need to be adaptable."

Emotional intelligence

Finally, emotional intelligence is key.

"Especially when you're supporting somebody as a personal assistant," says Levine, "you're in the most intimate sort of space in their lives, their home, their family, their pets, their spouses, their kids." These are private, vulnerable settings. It's critical to know what's appropriate to say and how to act in them.

Plus, again, the job happens throughout the day, not just in that typical 9-to-5 window.

"Being able to really get to know the way that your boss moves throughout the day, not just logistically, but also their emotions, their stress levels" is key, Levine says. Having that emotional intelligence will then inform when it's appropriate to bring up certain elements of the job.

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