Early in his career, Kiesler was assistant conductor of the Indianapolis Symphony, music director of the South Bend Symphony and principal conductor of the Congress of Strings and the Saint Cecilia Orchestra where his “Tribute to Shostakovich” and national broadcasts brought widespread acclaim. Kiesler was the recipient of the 1988 Helen M. Thompson Award, presented by the American Symphony Orchestra League to the outstanding American music director under the age of 35. He was one of three selected for the Leonard Bernstein American Conductors Program, and conducted the Ensemble Intercontemporain in sessions led by Pierre Boulez for the centenary of Carnegie Hall. At the 1986 Stokowski Competition, he was awarded the Silver Medal by Maurice Abravanel, and special recognition for best performance of Appalachian Spring, by Morton Gould. Kiesler's performances are heard on a dozen recordings on the Naxos, Dorian, and Equilibrium labels with the BBC in London, Third Angle, and the University Symphony Orchestra and University Opera Theatre. Evan Chambers’ orchestral song cycle, The Old Burying Ground, was released on the Dorian Sono Luminus label in 2010. Gramophone Magazine praised, "The performance is a luminous reflection of Chambers' sympathetic vision. Kenneth Kiesler shapes the score with a keen ear for balance, pacing and nuance...” His frequent opera conducting includes Bright Sheng’s The Silver River in Singapore, Britten's Peter Grimes and Rossini’s Il Turco in Italia at the Opera Theatre of St. Louis, Carmina Burana at Syracuse Opera and operas of Puccini, Verdi, and Mozart. His dance performances include Appalachian Spring with Martha Graham, and Cinderella with the Indianapolis Ballet. He has led premieres by Evan Chambers, Steven Stucky, Gunther Schuller, Leslie Bassett, Ben Johnston, Aharon Harlap, Gabriela Lena Frank, Kristin Kuster, Steven Rush, and Paul Brantley. At the age of 19, he conducted the first performance since 1925 of Gershwin's original jazz-band score of Rhapsody in Blue. At Michigan, he conducted the U.S. premiere of Mendelssohn's Third Piano Concerto, the world premiere of James P. Johnson's The Dreamy Kid, and the first performance since 1940 of Johnson's blues opera, De Organizer.