The impact of Bill Mack's art is achieved not only by his dramatic portrayal of the human form, but also by the utilization of a wide variety of materials with which to execute his artistic vision. The final work emerges as a classic example of the interplay of form and materials. For over 35 years, Bill Mack has created sculpture in relief and in the round for government, corporate and private collections. His art hangs in galleries in four continents and he has had exhibits in Tokyo, England, France and Germany. In reference to his interest in relief sculpture, Mack states, "A lot of sculptors have no reason to do it and they just don't develop in that direction. I've had to actually re-work pieces by some teachers of sculpture and some sculptors of note who do all their work in the round and for one reason or another, have difficulty doing something in relief. It's not like I'm tooting my own horn, but I know there's no one in the United States, or in the world, for that matter, who can technically do a relief portrait better than I can.