Walker is the founder of Media Training Worldwide and has been conducting public speaking training workshops and seminars since 1984. Walker has trained Presidents of countries, Prime Ministers, Nobel Peace Prize winners, Super Bowl winners, US Senators, Miss Universes and Members of Parliament. He has conducted presentation and media training workshops on six continents in more than two dozen countries. His book, "Secret to Foolproof Presentations" was a USA Today # 1 Bestseller, as well as a Wall Street Journal, and Business Week Bestseller.