David Miller invested 34 years in the medical equipment industry, with the final 20 as President and CEO of The MED Group. Under his leadership, the company relocated from a Chicago suburb to his hometown of Lubbock, Texas, and expanded from 27 locations to over 800 nationwide.

In the winter of 1999, while navigating a serious business challenge, David experienced a life-altering moment during a time of quiet reflection. In what he believes was the voice of God, he heard the words, “Just walk away and I’ll take care of you.” Despite enjoying professional success, financial security, and leading a company that served thousands of physically challenged individuals across the country, David followed that calling. That pivotal decision would lead to a profound transformation in his life, a journey he details in his book The Four Cornerstones and the Capstone.

Raised on the South Plains of West Texas, David earned his business degree from Texas Tech University, where he humorously notes he majored in fraternity life and minored in intramural sports. He was married to Jayne Ann Williston of Austin for over 40 years before her passing from cancer. He is now married to Katherine McKelvy, and the couple resides in Horseshoe Bay, Texas. Together they share four children—Tim, Matt, Beth, and Summer—and nine grandchildren.

In 2005, David co-founded Spirit Ranch in Lubbock, Texas, alongside James Cutrera. Spirit Ranch served as a leadership and team development retreat, incorporating equine-assisted learning, high ropes challenge courses, and the beauty of a hidden canyon to help individuals and teams transform their perspectives. In its first decade, the Ranch hosted and developed over 30,000 guests, all while upholding its vision of bringing others closer to their Creator and its mission of building believers, leaders, and teams.

David’s influence extends beyond business and leadership retreats. He has served in diverse roles—from Mayor of Lubbock to little league coach—and believes leadership can be exercised at every level. Now in what he calls the “4th quarter” of his life, David is committed to paying forward timeless leadership principles through personal coaching, group facilitation, and inspirational speaking under his company, Cornerstone Executives.

David Miller continues to inspire others by sharing his story of faith, leadership, and transformation—encouraging people to listen to God’s call, step boldly into new seasons, and lead with integrity and purpose.