Egerton is widely considered to be one of the most important writers in the late nineteenth century New Woman movement, and a key exponent of early modernism in English-language literature.

A second marriage (in 1891) to the minor adventurer and author Egerton Tertius Clairmonte was the impetus for her first attempts at writing fiction – instigated by his penniless status and her desire to alleviate the boredom she felt upon her return to rural Ireland.

"[8] Egerton's first book of short stories, Keynotes, was published by John Lane and Elkin Mathews of the Bodley Head in 1893 and illustrated by Aubrey Beardsley.

Keynotes was phenomenally successful (and notorious) on both sides of the Atlantic and as a result of this Egerton became a celebrity, was interviewed in the leading magazines of the day, and was famously lampooned in Punch.

[9] Keynotes and her subsequent fiction often had the same thematic preoccupation: a dismissal of female purity as a male construct that denies women the right to expect and experience sexual freedom and fulfilment.

[6] Commentators long felt that Keynotes was the high-water mark of Egerton's literary career, but a renewed interest in her later work gained momentum in the first decade of the twenty-first century and has continued apace.

Egerton's work is among the most forthrightly outspoken in nineteenth-century and early twentieth-century English-language literature in terms of a demand for women's education, financial independence, and sexual freedom [citation needed].

Interestingly, like Emily Lawless, Egerton was one of the major feminist writers of the period who chose to distance herself from the women's suffrage movement, although in her private letters she could be forthrightly pro-suffrage.

She was scathing of marriage as an institution, and many of her protagonists overtly defy Victorian and Christian morality by advocating free unions, same sex parenting partnerships and single parenthood.

Egerton's stylistic innovations and her often radical and feminist subject matter[11] have ensured that her fiction continues to generate academic interest in America and Britain.