Engel is founder and president of Development Associates International and retired distinguished professor in the graduate programs at Eastern University, where he founded the Center for Organizational Excellence. He has ministered around the world as a consultant, trainer and leadership-development expert and is well known for his books and writings on world evangelization.
Roger Blackwell, founder of the marketing consulting firm Roger Blackwell & Associates, is a sought-after speaker & the author of "From Mind to Market" & the classic textbook "Consumer Behavior".