When you're choosing a key employee, a partner in an important project, or even a potential boss, what traits should you seek out?

Former U.S. President Barack Obama has some great insights on this question. In his memoir, "A Promised Land," he details the qualities that led him to choose current President Joe Biden as his running mate in his 2008 campaign.

They were both Democratic senators, but other than that, Obama writes, "we couldn't have been more different." Obama was born in Hawaii and had lived in Indonesia. Biden was born in Scranton, Pennsylvania and spent most of his life in Delaware.

Obama was cerebral and reserved, later nicknamed "No-Drama Obama." Biden was "all warmth" and talkative. Obama was running as a newcomer to politics; Biden had been in the Senate for 35 years. Obama is supremely disciplined in all his public communications, whereas Biden, Obama observes, is a "man without inhibitions, happy to share whatever popped into his head."

Perhaps most significant of all, there was another potential candidate in the mix, Virginia senator Tim Kaine, who later became Hillary Clinton's running mate. Obama and Kaine were good friends, had similar resumes, and, Obama writes, similar temperaments. Kaine had also been an early key supporter of Obama's campaign and worked hard for him, while Biden had run against him. There were so many good reasons to choose Kaine.

Why pick Biden instead?

The decision was, in part, a political calculation. Obama and his advisors thought people who were uncomfortable voting for a relative newcomer would be reassured by the presence of such a senior senator on the ticket.

But there was a lot more to it than that. As he got to know Biden, Obama discovered qualities he knew made Biden the right choice — and they are qualities that everyone should consider when choosing someone to be on your team:

1. He was diligent.

"On domestic issues, he was smart, practical, and did his homework," according to Obama. "His experience in foreign policy was broad and deep."

During Biden's brief presidential run, Obama writes, "he had impressed me with his skill and discipline as a debater and his comfort on a national stage."

Obama knew how much work it took to be as knowledgeable and effective as Biden was and that he could count on Biden in a pinch. "I liked the fact that Joe would be more than ready to serve as president if something happened to me," he writes.

2. He had grit.

Biden stuttered from when he was in grade school to when he was in his 20s. Public speaking was terrifying for him. His classmates — and a strikingly insensitive nun — made fun of him. As a small child, he worked with a speech pathologist, but it didn't help.

Still, Biden was determined that the stutter wouldn't hold him back in life. He kept working at it and finally learned to control it by memorizing lengthy passages of Irish poetry and reciting them in front of the mirror.

Biden had the stutter more or less under control when he entered law school.

3. He was resilient.

In 1972, shortly after being elected to the Senate for the first time, Biden's first wife Neilia and 13-month-old daughter Naomi were killed, and his two sons were injured, in a car accident.

After considering quitting his Senate seat, Biden decided to continue living in Wilmington, Delaware to avoid any further disruption to his sons' lives. He commuted to the Capitol daily via Amtrak, a practice he kept up throughout his Senate career.

Then in 1988, shortly after he dropped out of his first presidential race, Biden suffered two brain aneurysms that required surgery and kept him away from work for seven months.

Despite all these setbacks, Biden remained warm, optimistic and upbeat. "Family had sustained Joe, but so, too, had a buoyancy of character," Obama explains in his memoir. "Tragedy and setbacks may have scarred him, I would learn, but they hadn't made him bitter or cynical."

4. He passed the gut check.

"What mattered most," according to Obama, "was what my gut told me — that Joe was decent, honest, and loyal. I believed that he cared about ordinary people, and that when things got tough, I could trust him."

Sentiments or judgments that you can't explain are always worth some examination. Do you trust someone more who reminds you of your favorite high school teacher, or dislike someone who resembles an ex-partner? Do you gravitate toward people who seem to have the same background that you do?

It's worth asking yourself these questions. But when choosing someone to be on your team, listening to what your gut tells you just makes sense. Your intuition and your experience will help you figure out who will be a good fit with you and who won't be.

So rely on your gut, as Obama did, to help steer you to the right choice.

Minda Zetlin is a freelance writer covering business, money and leadership. She is also the co-author of "The Geek Gap" and former president of the American Society of Journalists and Authors. Follow her on Twitter @MindaZetlin.

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