A leader in student politics during her college years, Sahgal followed her mother and sisters in brief prison terms for demonstrating against the British Raj.
Between 1930 and 1935, Sahgal finished college, became a teacher and was a member of the revolutionary Indian National Congress.
In 1935, she married a government bureaucrat and, she explains, had to give up politics as well as active association with her old friends.
Sahgal joined various ladies clubs and volunteer welfare organizations: as a member of the Catering Advisory Committee for the North Eastern Railway, she investigated charges against crooked vendors at train stations.
She made an unsuccessful run for public office in a New Delhi by-election in 1961, she was supported by the Swatantra Party under Sir Sobha Singh, though an inter-party coup led by the Socialist manager of the Delhi Swatantra Party led to her loss.