Born in Schwabmünchen, Germany in 1931, Seitz graduated from Hochschule für Gestaltung Ulm (Ulm School of Design) with a diploma in Visual Communication in 1959, after studying with Tomás Maldonado, Max Bill, and Otl Aicher.
He then received a Master of Fine Arts (MFA) in Graphic Design and Photography from Yale University in 1961, studying with Paul Rand, Bradbury Thompson and Herbert Matter.
[1] In 1968, opened his first graphic design firm, Visual Communication, Inc., as a solo practitioner.
In 1970, Seitz joined Dewey Thorbeck and Al French (architecture), Roger Martin (landscape architecture), and Steve Kahne (computer specialist) in launching InterDesign, the Twin Cities’ first interdisciplinary design firm.
Major InterDesign projects include: the identity programs and signage systems for the Minneapolis Parkways, the downtown St. Paul Skyways, the Minnesota State Capitol and the Minnesota Zoo.