Moss began her career in the federal government as a dessert cook in government cafeterias. In 1945, she moved to a job as a clerk in the General Accounting Office and in 1949 secured a civil-service position as an Army Signal Corps communications clerk at the Pentagon. A widowed mother, Moss had steadily improved her position since moving to Washington, DC, in the early 1940s. She bought a home in 1950, and by 1954 had an annual income of $3,300 (about $ today)