Her interest in politics was established early and she joined the Junior Imperial League at the age of sixteen.

The following year she was invited to join the Conservative Party's supporting team of speakers for the 1931 election campaign.

In 1941 she took a job in the civil service as Principal Private Secretary to Lord Selborne, the minister of economic warfare, a post she held until the end of the war.

[3] She was re-elected at the next four general elections (1951, 1955, 1959, 1964), served as Parliamentary Secretary 1951 – 1957[4] and was made a Privy Counsellor in 1959.

[3] Lady Hornsby Smith was portrayed in the 2008 drama The Long Walk to Finchley (by actress Sylvestra Le Touzel).