With senior partners August Diglas and Emmerich Hanus, the studio created such German-language classics as Die Glücksmühle (The Mill of Happiness, 1946), Dr. Rosin (1949), and Märchen vom Glück (Kiss Me, Casanova, 1949), and gave Gunther Philipp and Nadja Tiller their first screen roles. She starred in operas, operettas, theatrical dramas and comedies, helped initiate several theater groups, was announcer for Allied Forces Broadcasting and the BBC, toured West Germany in a one-woman-show and gave master classes in voice and piano. During this period, Dassanowsky also modeled exclusively for Austrian painter Franz Xaver Wolf (1896–1990), whose work featuring her image is now in museum and private collections. An expert in the Ignace Paderewski piano technique, her musical pedagogy continued in the 1950s in Canada and New York, where she also married and had a son and daughter. At this time she turned to design and created a prototype for woman's leather day coat, which is now in the collection of the MAK-The Museum of Applied Arts in Vienna. She later divorced and her marriage was annulled. Although she never remarried, she was briefly linked with author and actor, Prince Heinrich Starhemberg (aka Henry Gregor, 1934-1997) in the mid 1990s.
In Hollywood in the 1960s, she resisted becoming a trendy Euro-starlet and preferred to remain behind the camera as a vocal coach for director/producer Otto Preminger. In 1962, she became a naturalized citizen of the United States. A successful Los Angeles businesswoman, in 1999, she re-established Belvedere Film as a Los Angeles/Vienna-based production company with her son, Robert. She was executive producer of the award-winning dramatic short film, Semmelweis (2001), the spy-comedy, Wilson Chance (2005), and several works in progress at the time of her passing, including the documentary The Archduke and Herbert Hinkel (due to be released in 2008).
Recognized internationally for her unique work as a pioneering woman in film production and as a multi-talent in postwar Austrian arts and culture, von Dassanowsky is the only Austrian woman to receive the Women’s International Center’s prestigious Living Legacy Award, and has been honored with the UNESCO Mozart Medal, the Austrian Decoration of Merit, the French Ordre des Arts et des Lettres, the Austrian Film Archive's Lifetime Achievement Medal, by the State of California and the cities of Vienna and Los Angeles, where von Dassanowsky lived since 1962. Additionally, she is reported to have been nominated for the honorary Right Livelihood Award in the late 1990s.