Dr. Chuback and Cameron Chuback discuss a very important mentor, Dr. George Constantinopoulos (Dr. C). It was under the guide of Dr. Constantinopoulos that Dr. Chuback learned a great lesson. One can have access to a great teacher with great lessons to share, but unless there is a willingness to learn the lessons are pointless. Dr. C was a bit of a taskmaster that no one wanted to work with. When Dr. Chuback had the opportunity to work under Dr. C he acquired an amazing amount of experience that helped shape his career. In this chapter, we explore great teachers with great lessons and the fortune to be ready to accept this amazing knowledge.