I recently went one-on-one with David Joosten, President and Chairman of Vodafone Business US.

Adam: Thanks again for taking the time to share your advice. First things first, though, I am sure readers would love to learn more about you. How did you get here? What experiences, failures, setbacks, or challenges have been most instrumental to your growth?

David: My journey has been defined by a mix of experiences, setbacks, and challenges that shaped me into the leader I am today. I learned early on that I thrive in competitive environments, whether in business or sports. This competitive drive has helped me navigate challenging markets where success is not guaranteed. And led me to take my current role in leading Vodafone Business Americas. 

I owe much of my growth to the opportunities for personal development provided by my organization, which has a strong ethos of promoting talent from within. Working in the telecom industry—an environment that has faced significant disruption over the years—has taught me resilience and adaptability. Each challenge has reinforced the importance of staying focused on growth and reinvention. 

Adam: In your experience, what are the keys to leading large international businesses?

David: Leading an international business requires a balance of strong vision and trust in your team. I focus on surrounding myself with the best talent, delegating authority, and maintaining clear communication through regular check-ins. Setting high standards is essential, but it’s equally important to create a culture of accountability and recognition. Flexibility is another key factor—adapting to different markets and cultures while staying aligned with core goals and values ensures consistency across the board. Above all, delivering measurable results builds trust and sets the foundation for sustainable growth.

Adam: What do you believe are the defining qualities of an effective leader?

David: I believe effective leaders demonstrate candor, integrity, humility, and active listening. They are empathetic and responsive to the needs of those they lead and they are consistent in how they show up for their employees every day. A leader must reflect both the company's values and their personal values, creating a transparent and inspiring example for others to follow. Delivering measurable results is critical to building trust and confidence, both within teams and with stakeholders. 

Adam: How can leaders and aspiring leaders take their leadership skills to the next level?

David: It starts with listening—really listening—and using every tool at your disposal to stay connected with your team. Take time to reflect on your decisions and actions regularly. High standards are critical for sustainable growth, so set ambitious goals and challenge your organization to achieve them. At the same time, create an environment where people feel valued, supported, and motivated. Growth isn’t just about hitting targets; it’s about fostering a culture where people can thrive.

Adam: What is your best advice on building, leading, and managing teams?

David: Strong teams are built on recognition, development, and support. People need to feel like their contributions matter and that they’re being challenged in meaningful ways. Employee satisfaction is directly tied to business success—if your people aren’t happy, the business won’t grow. As a leader, how you present yourself matters. Be honest, reflective, and transparent about your own strengths and areas for improvement. When you model that openness, it encourages others to do the same and creates a culture of trust and collaboration.

Adam: What are your three best tips applicable to entrepreneurs, executives, and civic leaders?

David: Customer Obsession: Understand your customers deeply and let their needs drive your agenda. Focus on pragmatic solutions that enhance customer satisfaction and drive sales.

Pragmatic Leadership: Take calculated, practical steps that align with your objectives while staying adaptable in competitive markets.

Employee Empowerment: Invest in your teams by providing the tools and opportunities they need to succeed while holding them to high standards.

Adam: What are the most important trends in technology that leaders should be aware of and understand? What should they understand about them?

David: Technology upgrades alone aren’t enough to stay competitive. Leaders must focus on creating smarter, more efficient, and productive operating environments while addressing infrastructural barriers. Customer-centricity remains at the heart of success, with a strong emphasis on aligning technological advancements to meet customer needs and improve satisfaction. 

Adam: What are your best tips on the topics of sales, marketing, and branding?

David: Successful sales and marketing require a deep understanding of customer objectives and challenges. Interact with customers frequently to uncover opportunities for innovation and refine your strategy. By aligning your solutions with their needs, you can build trust and deliver results. Branding should reflect a commitment to customer satisfaction, creating a strong connection between your organization and the market. 

Adam: What is the single best piece of advice you have ever received?

David: “Listen more than you speak.” It’s simple but incredibly powerful. Listening helps you understand others, build relationships, and make better decisions.


Adam Mendler is an entrepreneur, writer, speaker, educator, and nationally recognized authority on leadership. Adam is the creator and host of the business and leadership podcast Thirty Minute Mentors, where he goes one-on-one with America's most successful people - Fortune 500 CEOs, founders of household name companies, Hall of Fame and Olympic gold medal-winning athletes, political and military leaders - for intimate half-hour conversations each week. A top leadership speaker, Adam draws upon his insights building and leading businesses and interviewing hundreds of America's top leaders as a top keynote speaker to businesses, universities, and non-profit organizations. Adam has written extensively on leadership and related topics, having authored over 70 articles published in major media outlets including Forbes, Inc. and HuffPost, and has conducted more than 500 one on one interviews with America’s top leaders through his collective media projects. Adam teaches graduate-level courses on leadership at UCLA and is an advisor to numerous companies and leaders. A Los Angeles native, Adam is a lifelong Angels fan and an avid backgammon player.

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