While Walter Miller worked in his father’s electronics store to pay for medical school, he became fascinated with the technical side of television while repairing old sets. He decided not to become a doctor and began a job as the lighting director for the variety series The Horn and Hardart Children's Hour in the late 1940s on NBC. Miller eventually worked his way up to a staff director at the station when he began directing the classical music-centered variety series, The Bell Telephone Hour. While at NBC he directed numerous music and variety specials throughout his career, including those for Dick Clark, Barbra Streisand, Rodney Dangerfield, Anne Bancroft, Johnny Cash, Frank Sinatra, George Burns, Stevie Wonder, Steven Wright, Sam Kinison, and Kathie Lee Gifford, among others, as well as several broadcasts of the Macy’s Thanksgiving Day Parade.
In 1977 he directed his first major awards show, the 4th Annual Daytime Emmy Awards. This led into a long career directing award shows which include the Tonys, Primetime Emmys, Grammys, Latin Grammys, People’s Choice Awards, and the Country Music Association Awards for which he received an honorary award for directing and/or producing the broadcast for over 40 years. In addition to his large body of musical and variety specials, Miller also directed episodes of the television series The ABC Afternoon Playbreak, The Lost Saucer, Electra Woman and Dyna Girl, All in the Family, Detective School, and Fame.
For his directorial achievements, Miller has won three DGA Awards for Musical Variety, for the Statue of Liberty celebration Liberty Weekend in 1987, the 100th Birthday Celebration of Irving Berlin in 1989, and the Tony Awards in 1992. Miller has also been nominated for 19 Primetime Emmy Awards, winning five, four of which for broadcasts of the Tony Awards (1993, 1994, 1998, 1999) and the television special 'S Wonderful, 'S Marvelous, 'S Gershwin in 1972.