A vibrant and thriving company culture doesn’t just happen. It takes a tremendous amount of attention, and it has to be modeled by the senior leadership team. Culture starts at the top, and employees need to see it in their leaders. If they don’t, any progress made won’t be sustainable.

When I started at Humana (HUM) in 2013, my health wasn’t where I wanted it to be. I wasn’t eating right or exercising as much as I should have. And for a healthcare company like Humana—with the dream to help people achieve lifelong well-being—it’s essential to live that in our daily lives, at work and at home.

But as I really dug into the job and began working with President and CEO Bruce Broussard to build a team that embodied our culture, I knew I had to start with myself. I had to take an honest look at my own habits—the way I lived my life personally and professionally—and start modeling the behavior that we needed for the larger team. I’ve changed the way I eat, I exercise more, I feel terrific, and I now talk about health openly with my teammates.

Being wide open and transparent with your team members is key, and the payoff is immense. People believe in you, they trust you, and they want to work in an environment of honesty and authenticity.

In 2013, when Bruce became CEO, he quickly set about building his senior leadership team. There were some great candidates, and Bruce knew they could do the technical parts of the jobs, but he would never compromise on cultural fit.

See also: What 23 years at the same company taught this CEO

We built culture into the performance-management system, holding people accountable for their behavior and judging their contributions to the team. Bruce and the leadership team developed five principles for Humana to use: inspire health; cultivate uniqueness—respecting different perspectives and listening with open minds; rethink routine to make sure we’re innovating and sparking creativity; pioneer simplicity to make life easier and inspire an agile organization; and thrive together by breaking down silos, inviting collaboration and mentoring one another.

Earlier this year, we announced an ambitious goal to improve the health of the communities we serve by 20% by 2020. To achieve this goal, we will need to marshal the collective strength of all 50,000 Humana associates. And the only way to do that is to lead by example, from the CEO and throughout the organization.

Every business has its own culture, whether you manage it or not. We get the culture we’re willing to accept. So why not only accept the best?

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