Zack has had songs recorded by Joan Baez, Jerry Lee Lewis, Waylon Jennings, Joe Sun, Jessie Colter, Marty Robbins, and the blues group, the Cornelius Brothers and Sister Rose. Actor/Director Dennis Hopper included Zack's song "Sympathetic Scarecrow" in the film THE LAST MOVIE. After a huge success with EASY RIDER, he invited Zack to live with him in Taos, New Mexico where he appeared as Dennis' side-kick troubadour in the movie THE AMERICAN DREAMER. He has been on the road with Bob Dylan, Waylon Jennings, Joan Baez, Willie Nelson and Kris Kristofferson.
Early in his career, Zack came to Nashville and signed as a staff writer with Buckhorn Music Co. along with Kris Kristofferson. In 1970 he signed with Cedarwood Publishing under the direction of J. William Denny. During the "out-law" era of country music Zack spent two years as a creative manager for Tompall Glaser's company, Glaser Music, and Waylon Jennings' company, Baron Music. In addition, Zack worked with Mel Tillis as a staff writer at Saw Grass Music Co. Currently all of these companies are part of Universal Music Group. Zack has recorded several albums of his original material. Performing with his band, he has ventured from Nashville to Austin, Houston, and Fort Worth, Texas; Los Angeles, Ca.; Washington, DC; Philadelphia, Pa. and several of New York City's hottest clubs. Currently he is performing with his band in Nashville clubs while writing music and recording another album.