Fostering the right culture is essential to a company’s success. It takes leadership, commitment and time. It requires having a vision of what the company should be, and then aligning values, behaviors and strategy to that vision in an authentic way. Customers today want companies to stand for something more than just making money. They want to see companies give back to society, contribute to communities, make a positive difference in people’s lives, and understand their needs. And the companies that do those things — connect with customers on a personal and emotional level — are the companies that will be the most successful in the long run.

At Lowe’s (LOW), for example, we know that what we do matters to people. We help people love where they live — and we do that by putting customers first and supporting them with the projects that improve their homes. We aspire to be a purpose-driven, customer-centric, service-minded company, and we have to ensure that our values — the things that are important to us — and our day-to-day behaviors are all driving us toward that vision.

The first step to building culture is always to look inward. Review every process and policy, and examine every part of business to ensure they are consistent with your values. Listen intently — to customers, partners and employees — and then respond to their needs. Hold everyone accountable when an action or a decision keeps you from the culture you’re striving to create.

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That’s the hard part about building a culture — not allowing individual agendas or competing priorities to get in the way. Leadership is key to staying on that path. It starts with leaders who want to be a part of something bigger than themselves and who inspire others to do the same. It’s up to leaders to show that every person is indispensable to the company. Leaders make or break a company’s culture, and if they’re saying one thing while doing another, the effects on culture are devastating. For that reason, accountability is critical, and everyone has to be empowered to call it out when they see it.

Accountability requires courage and conviction — two things that typically come from having passion for your work. In my experience, passion has always been the secret ingredient to building a culture, because a passionate and engaged workforce can move mountains. People in that culture bring the best ideas, adapt the fastest, and drive results that couldn’t be achieved otherwise.

Culture doesn’t happen overnight, and it doesn’t happen on a project timeline or self-imposed deadline. It happens over time, and it happens when the company invests time in celebrating wins along the way. Celebration is important to us at Lowe’s, and we celebrate wins both big and small. It keeps people inspired, engaged and passionate about the work they’re doing, and allows a culture to emerge over time that’s in tune with the company’s values and behaviors.

Read all answers to the Fortune 500 Insider question: How do you build a company’s culture?

You get the company culture you are willing to accept by Tim Huval, senior vice president and chief human resources officer at Humana.

What 23 years at the same company taught this CEO by Alan Colberg, president and CEO of Assurant.

What a tornado taught this team about workplace culture by Deb Aldredge, chief administrative officer of Farmers Insurance.

So you messed up at work. Here’s what you do next by Val DiFebo, CEO of Deutsch New York.

How Wells Fargo’s CEO built the team at the world’s most valuable bank by John Stumpf, chairman, president and CEO of Wells Fargo & Company.