As the executive vice president of Babel Networks US, Martesko-Fenster led the film and animation division for Babelgum, the global web, mobile and IPTV destination.
[3] During his five-year tenure he supervised the strategic re-organization of the film division and oversaw the company's successful theatrical releases of Scratch and Sex and Lucia.
In the late 1980s, Martesko-Fenster was a coordinating producer for Great Performances Music on PBS and produced over 20 music television programs and five live satellite broadcasts, including; Gala of Stars, James Levine's Mozart in Salzburg, Celebrating Gershwin: S’Wonderful & The Jazz Age, Herbert von Karajan's Don Giovanni, Hal Prince's Madama Butterfly, Pavarotti Returns to Naples and From Vienna: The New Year's Celebration with Walter Cronkite.
He is credited as a producer on Benjamin Jonathan Bergmann'as Gelato and Mau and Thomas Wirthensohn’s upcoming Mystic Business and Homme Less (2014 DOC NYC Grand Jury Award Winner), and Maura Axelrod’s Maurizio Cattelan – Be Right Back.
[14] He was a special consultant on Kevin Kerslake's As I Am: The Life and Times of DJ AM, and past projects include Frank Dead Souls, Scenes From The New World, Myth or Reality: The von Trapp Family and Vienna 1900.