Draftsman, James M. Taylor, Jr., Architect, Seattle, WA, 1938; Draftsman, John T. Jacobsen, Architect, Seattle, WA, 1938; Draftsman, Frederick V. Lockman, Architect, Seattle, WA, 1939; Draftsman, B.Marcus Priteca, Architect, Seattle, WA, c. 1939; Designer, John Graham and Company, Seattle, WA, 1939; Assistant District Architect, Austin Company, Seattle, WA, 1940-1945; the Austin Company, a huge construction company based in Cleveland, OH, was known for its industrial architecture; during World War II, he worked on defense projects for Austin. Principal, John A. Rohrer, Architect, Seattle, WA, 1946-1951; Rohrer maintained an office at 201 Railway Exchange Building in Seattle from 1946-1951; Designer and Illustrator, Naramore, Bain, Brady, and Johanson, Seattle, WA, c. 1955; Rohrer worked as a consultant to a number of firms in Seattle, rendering presentation drawings.

Instructor in Basic Design and Illustration, University of Washington School of Architecture, 1948-;

Member, American Institute of Architects (AIA), Washington State Chapter; Member, AIA Washington, Awards Committee, 1950; he resuscitated the AIA Washington Honors Award program, working with committee colleagues Fred Bassetti (b. 1917) and Victor Steinbrueck (1911-1985).

Elected to Tau Sigma Delta, 1954;

Graduate, Queen Anne High School, Seattle, WA, 1929; B.Arch., University of Washington, Seattle, WA, 1937.

Rohrer served as the Sous-Massier of the UW Architecture Department's Student Atelier in 1936.

Rohrer was born in Seattle, WA, in 1914, and lived during his youth in the Queen Anne Neighborhood; he graduated from Queen Anne High School in 1929. He died in Seattle, WA, in 2004.

John Rohrer married Ruth Campbell Williams (b. 1918) in 1938. Ruth was, like her husband, a Seattle native and also an architecture student at the University of Washington. She started her architectural training there in 1936. A UW architecture school classmate of Rohrer's, the noted architect Paul Hayden Kirk (1914-1995), served as Rohrer's best man.

He and Ruth had two children.

During 1946, Rohrer practiced in an office building located at Cherry Street and Second Avenue nearby by to his friends, Paul Hayden Kirk and James Chiarelli. The three maintained a loose association during the 1940s, cooperating on large-scale projects.