Since the 1970s, Maxwell has led churches in Indiana, Ohio, California, and Florida. After serving as senior pastor for 14 years, he left Skyline Church in 1995. In 2004 he returned to congregational ministry at Christ Fellowship in Palm Beach Gardens, Florida, where he is currently a teaching pastor. On November 16, 2008, he began serving as a guest pastor at Crystal Cathedral in Orange County, California. His mentor, Robert H. Schuller, had a variety of noted evangelical pastors preach at his megachurch after his son, Robert A. Schuller, resigned as senior pastor in 2008. Maxwell returned to preach at the Crystal Cathedral several times and his messages were broadcast on the Hour of Power television program.

Maxwell is a leadership expert, speaker, and author. He is the founder of INJOY, Maximum Impact, The John Maxwell Team, ISS and EQUIP. EQUIP is an international leadership development organiation working to help leaders, involved with leaders from more than 80 nations. Its mission is "to see effective Christian leaders fulfill the Great Commission in every nation".

Maxwell speaks annually to Fortune 500 companies, international government leaders, and organisations as diverse as the United States Military Academy at West Point and the National Football League. A New York Times, Wall Street Journal, and Business Week best-selling author, he was one of 25 authors named to Amazon.com's 10th Anniversary Hall of Fame. Three of his books, The 21 Irrefutable Laws of Leadership, Developing the Leader Within You, and The 21 Indispensable Qualities of a Leader, have each sold over a million copies.

In 2007 Maxwell was inducted into Omicron Delta Kappa at Concordia University Irvine. Maxwell has a building named after him and his family at Indiana Wesleyan University, the Maxwell Center for Business and Leadership, as a result of his influence on the Wesleyan Church, the owner of the university. In 2015, he was inducted into the IWU Society of World Changers, where he was honoured with an honorary doctorate degree.

Maxwell was a keynote speaker at National Agents Alliance NAA Leadership Conference several times, most recently in 2010.Maxwell was the keynote speaker for the Symmetry Financial Group's National Conference in February 2018. In 2012 he was awarded the Golden Gavel by Toastmasters International.

In July 2013, Maxwell's organisation trained 24,000 leaders in Guatemala. Randy Stroman and other John Maxwell Team members took part in the weeklong leadership training sessions.

In May 2014, Maxwell was named the No. 1 leadership and management expert in the world by Inc. Magazine.