Ragen’s first three novels, which described the lives of ultra-Orthodox Jewish women in Israel and the United States, dealt with themes that had not previously been addressed in that society's literature: wife-abuse (Jephte’s Daughter: 1989), adultery (Sotah: 1992) and rape (The Sacrifice of Tamar: 1995). Reaction to these novels in the Orthodox and ultra-Orthodox communities was mixed. Some hailed her as a pioneer who for the first time exposed and opened to public discussion problems which the communities had preferred to pretend did not exist, while others criticized her for “hanging out the dirty laundry” for everyone to see, thus embarrassing the rabbis who were believed by many to be effectively dealing with these problems “behind the scenes” and also putting “ammunition in the hands of the anti-Semites”.

Her next novel (The Ghost of Hannah Mendes: 1998) told the story of a Sephardic family brought back from the abyss of assimilation by the spirit of their ancestor Gracia Mendes (a true historical figure), a 16th century Portuguese crypto-Jew who risked her life and her considerable fortune to practice her religion in secret.

Chains Around the Grass (2002) is a semi-autobiographical novel of the author’s childhood which dealt with the failure of the American dream for her parents.

In The Covenant (2004) Ragen dealt with the contemporary theme of an ordinary family sucked into the horror of Islamic terrorism.

The Saturday Wife (2007), the story of a rabbi's wayward wife, is loosely based on Flaubert’s Madame Bovary, and is a satire of modern Jewish Orthodoxy.

Women’s Minyan, Ragen’s 2001 play, tells the story of an ultra-Orthodox woman who, upon fleeing from her adulterous and abusive husband, finds that he has manipulated the rabbinical courts to deprive her of the right to see or speak to her twelve children. The story is based on a true incident.

Women’s Minyan ran for six years in Habima (Israel's National Theatre) and has been staged in the United States, Canada and Argentina.

Ragen has long been active in the struggle to force rabbinical courts to uphold the dignity of women in divorce proceedings by solving the problem of the Agunah and by discontinuing the practice of allowing (and even encouraging) men to demand their wives give up their share of the couple’s joint assets in exchange for the divorce ("Get"). Little progress has been made on these issues.

More recently (2006), Ragen joined several other women in petitioning the courts to force the Israeli government and public bus companies to discontinue the gender segregated buses, in which women are required to sit in the rear of the bus and be dressed in accordance with the rules of modesty in Judaism. Several women who have refused to do so have been physically assaulted by ultra-Orthodox vigilantes. Ragen became involved in the matter after she was harassed after accidentally boarding a mehadrin bus. The case has been slowly making its way through the court system.

In 2007, two American-Israeli writers accused Ragen of plagiarizing their works. Ragen vehemently denies both accusations, putting them down to extortion and political agendas.