In 1950, Youngerman had his first group exhibition, Les Mains eblouies at Galerie Maeght in Paris, which also included Pierre Alechinsky, Eduardo Chillida and Corneille.
He met Alexander Calder through his father-in-law, Henri Seyrig, a renowned archaeologist and cultural attache to the Free French delegation to the United States.
During this time he became interested in the resurgence of geometric abstraction in Paris, especially in exhibitions such as Salon des Réalités Nouvelles which included Max Bill, Auguste Herbin and Richard Lohse.
Youngerman's exposure to the contemporary art in post-war France was critical to his development; he introduced aspects of geometric abstraction and Constructivism into his painting.
The American art dealer Betty Parsons visited Youngerman's Paris studio that summer, where she encouraged him to move to New York City.
In December 1956, he returned to the U.S. with his wife, Delphine Seyrig, and son; they rented a space in lower Manhattan's Coenties Slip, an area of largely abandoned loft buildings that would become a legendary artists' colony.
In 1959, Youngerman was featured alongside Johns, Frank Stella, and Kelly in Sixteen Americans, a landmark exhibition curated by Dorothy Miller at the Museum of Modern Art.