9 of the most inspiring acts of leadership

Leadership may not have a one-size-fits-all definition, but most acts of leadership do share a common goal: inspiring change. Fortune asked several executives to define what leadership means to them and which recent (and historical) acts of leadership have inspired them most. The following are their edited answers.

Denise Morrison, president and CEO of Campbell Soup Company

Define leadership:

Leadership is service to others. There is power in helping people get excited about what they do, and inspiring and motivating them to unleash their full potential.

What act of leadership has impressed you recently?

Through his deferential, yet decidedly determined demeanor, Pope Francis is not only setting a superior spiritual standard, but he is also leading a thorough transformation of the Catholic Church — rivaling any brand revitalization or corporate turnaround you could name.

What act in history best defines leadership?

On June 12, 1987, President Ronald Reagan stood at the Brandenburg Gate in West Berlin, Germany and said, “Mr. Gorbachev, tear down this wall!” Now, clearly, President Reagan’s words weren’t the only catalyst for the fall of the Berlin Wall, but no one can deny that his heartfelt leadership at a critical moment was a deciding factor in the demise of this despised communist icon.

Carol Sawdye, vice chairman and CFO of PricewaterhouseCoopers

Define leadership:

Leadership means setting your moral compass in the direction you know is right, even if it’s difficult or unpopular, and encouraging others to follow.

What act of leadership has impressed you recently?

Adam Silver, commissioner of the National Basketball Association (NBA) impressed me last year when he took a strong stand against racial discrimination, continuing an NBA tradition of leadership forged by his predecessor, David Stern.

What act in history best defines leadership?

Without a doubt, Rosa Parks is one of history’s greatest leaders. She had everything to lose when she refused to give up her seat on that bus 60 years ago. She took a huge risk and endured hatred and economic hardship.

Jennifer Hyman, co-founder and CEO of Rent the Runway

Define leadership:

Leadership starts with having a vision for a change you want to make in the world. Leaders show by example, and perhaps more importantly, empower others to be leaders of their own visions.

What act of leadership has impressed you recently?

I was blown away by Columbia University student Emma Sulkowicz and her efforts to change the conversation around sexual assault on college campuses. Her “Carry That Weight” senior thesis project turned a devastating personal experience into living art that finally laid bare an issue that has been shrouded in secrecy.

What act in history best defines leadership?

Bono and Bobby Shriver’s conception of RED. The plight of HIV/AIDS in Africa is one that can be discussed at nauseam, but rather than just focusing on the problem, RED leverages influence that already exists – that of iconic brands like Nike and Coca Cola – to stimulate consumer support to make a real change.

Ivanka Trump, EVP of development and acquisitions at Trump Organization

Define leadership:

Leadership is the ability to articulate a vision and unite a team of passionate people to bring that goal to life.

What act of leadership has impressed you recently?

My father, Donald Trump, is a man who stands by his convictions. He does not play both sides of the fence. His commitment to excellence and absolute refusal to accept anything less than the best has paid off in spades in his role as the head of the Trump Organization.

What act in history best defines leadership?

I am incredibly inspired by the leadership, courage, and determination shown by Malala Yousafzai. She was put on a kill list and shot by the Taliban in 2012, when she was just 15 years old. The young activist recovered, only to fight harder for girls’ rights to education.

Karen Kaplan, chairman and CEO of Hill Holliday

Define leadership:

True leadership changes the trajectory of a business or the course of history. Leadership is very different from management, which simply maintains the status quo.

What act of leadership has impressed you recently?

Pope Francis’ willingness to challenge tradition and bring humility and discussion back to Catholicism.

What act in history best defines leadership?

President John F. Kennedy staring down Soviet Nikita Khrushchev during the Cuban Missile Crisis.

Kat Cole, Group President of FOCUS Brands

Define leadership:

Leadership is believing in the future, yourself, others, and in a higher purpose. It’s about building culture, courage, and confidence through your actions and words and building teams that work to achieve common goals.

What act of leadership has impressed you recently?

Seeing our youth stand up and demonstrate great courage and compassion against the mistreatment of others – those who have led fundraisers and movements for great causes, against everything from bullying to cancer and in favor of inclusion and love. These simple acts are signs of leadership, of focusing on what really matters, and being willing to stand up for what’s right and engage others to do the same.

What act in history best defines leadership?

Nelson Mandela leading his country to a more free and equal future, an example of a leader committed to a higher purpose. He demonstrated resilience and forgiveness and an unwavering focus on unity – – all against incredible odds.

Anna Maria Chávez, CEO of Girl Scouts of the USA

Define leadership:

True leadership is about inspiration. It’s about having a vision, believing in that vision, and being willing to sacrifice for that vision in a way that inspires others to join you.

What act of leadership has impressed you recently?

The doctors and nurses on the front lines of the Ebola epidemic in West Africa. Their courage is boundless and they have been an inspiration to us all.

What act in history best defines leadership?

Perhaps I’m a bit biased, but I think the founder of the Girl Scouts Movement: Juliette Gordon Low. Before women had the right to vote in this country, Juliette had a vision of a movement that would be exclusively for girls, and through her dedication, dynamism, and tenacity, she inspired others to make her vision a reality. Today, 103 years later, we are continuing Low’s work, innovating and delivering a truly 21st century experience for girls, while remaining true to our core principles.

John Chambers, chairman and CEO of Cisco

Define leadership:

Leadership starts with setting a vision and strategy for your organization. Next, you need to recruit, develop, and retain talent to implement that vision and strategy. Finally, it’s a leader’s responsibility to walk the talk and then communicate all of the above.

What act of leadership has impressed you recently?

The grace demonstrated by the people of France after the Charlie Hebdo tragedies.

What act in history best defines leadership?

During economic downturns or dire circumstances is when true leadership is exhibited. Leaders need to be their best even in the worst circumstances, so I hold up Winston Churchill during World War II as one of the greatest leaders of our time.

Elizabeth Holmes, CEO of Theranos

Define leadership:

When I was headed to my first year at Stanford University, my father gave me a book: Meditations by Marcus Aurelius. In one of the essays, he writes, “that we came into the world for the sake of one another.” Leadership is devoting yourself completely to something that changes people’s lives.

What act of leadership has impressed you recently?

Dr. Kent Brantly, the first doctor to treat Ebola patients and return to the U.S. — he took the experimental drug ZMapp, gave his blood, and put his life on the line in service of others.

What act in history best defines leadership?

From the moment our country’s Constitution was written until the day the 19th Amendment was ratified, women never stopped fighting for their right to participate in our democracy. Each act of defiance and disruption in those 131 years of our history was leadership in its greatest form.

By Melanie Sena