in 2001 (Photo Courtesy of Caio Miguel)On November 12 th 2020, Jack Michael, one of the most prominent figures in the field of behavior analysis, passed away. For us, it is an honor and a privilege to write about someone who has influenced our careers as much as he did. He was a friend and role model who impacted how we teach, write, and think about behavior analysis. We worked under Jack's supervision during his last few years in academia, but many of his former students from other time periods have reported being heavily influenced by him in similar ways.Jack was a core faculty in the department of Psychology at Western Michigan University (WMU) from 1967 to 2003. During that time, Jack taught undergraduate courses on concepts and principles of behavior (with a rat lab), as well as graduate courses on Skinner's writings/radical behaviorism, verbal behavior,