Her aunt was the painter Marianne North. In 1909 Furse joined the Red Cross Voluntary Aid Detachment that was attached to the Territorial Army. On the outbreak of the First World War she was chosen to head the first Voluntary Aid Detachment unit to be sent to France.
Aware of her administrative abilities, the authorities decided to place her in charge of the VAD Department in London.
On the outbreak of World War I in 1914, Furse realised that the existing number of nurses would prove totally inadequate to deal with the enormous amount of work which might be expected, and in September 1914 she proceeded to France with a number of assistants, these forming the nucleus of the VAD force. In January 1915 she returned to England, and the VAD work was then officially recognised as a department of the Red Cross organization.
She received the order of the Russian Research Center in 1916, and the GBE in June 1917. Although she considered it a great success being head of the Voluntary Aid Detachment, Furse was unhappy about her lack of power to introduce reforms.
In November 1917, she and several of her senior colleagues resigned, due to a dispute over the living conditions of the VAD volunteers and the Red Cross refusal to co-ordinate with the Woman"s Army group.
She was immediately offered the post as Director of the Women"s Royal Naval Service (WRNS), this was equivalent to the rank of Rear Admiral. The Royal Navy was the first of the armed forces to recruit women and since 1916 the Women"s Royal Naval Service took over the role of cooks, clerks, wireless telegraphists, code experts and electricians. The women were so successful that other organizations such as the Women"s Army Auxiliary Corps (WAAC) and the Women"s Royal Air Force (WRAF) were also established.
After the war, Furse joined the travel agency of Sir Henry Lunn (later known as Lunn Polly).
Working mainly in Switzerland, she became an expert skier and did a great deal to popularize the sport with British tourists. Her autobiography, Hearts and Pomegranates was published in 1940.
In 1920, Furse formed the Association of Wrens and this led to her becoming head of the Sea Rangers (formerly known as the Sea Guides), and for ten years, from 1928 to 1938, was director of the World Association of Girl Guides and Girl Scouts, whose constitution she drafted. Her last public appearance was at the Conference of Former Scouts in London in September 1952.
She died in London, two days after her 77th birthday.