Daly retired from Boston College in 1999, after violating university policy by refusing to allow male students in her advanced women's studies classes.

[7] Early in her childhood, Daly had mystical experiences in which she felt the presence of divinity[weasel words] in nature.

[8] Daly taught classes at Boston College from 1967 to 1999, including courses in theology, feminist ethics, and patriarchy.

Daly was first threatened with dismissal when, following the publication of her first book, The Church and the Second Sex (1968), she was issued a terminal (fixed-length) contract.

As a result of support from the (then all-male) student body and the general public, however, Daly was ultimately granted tenure.

Daly's refusal to admit male students to some of her classes at Boston College also resulted in disciplinary action.

While Daly argued that their presence inhibited class discussion, Boston College took the view that her actions were in violation of title IX of federal law requiring the college to ensure that no person was excluded from an education program on the basis of sex, and of the university's own non-discrimination policy insisting that all courses be open to both male and female students.

[10] In 1998, a discrimination claim against the college by two male students was backed by the Center for Individual Rights, a libertarian advocacy group.

[11] Boston College removed her tenure rights, citing a verbal agreement by Daly to retire.

She brought suit against the college disputing violation of her tenure rights and claimed she was forced out against her will, but her request for an injunction was denied by Middlesex Superior Court Judge Martha Sosman.

Daly protested the commencement speech of Condoleezza Rice at Boston College, and she spoke on campuses around the United States as well as internationally.

[19] Often regarded as a foundational work in feminist theology, Beyond God the Father is her attempt to explain and overcome androcentrism in Western religion, and it is notable for its playful writing style and its attempt to rehabilitate "God-talk" for the women's liberation movement by critically building on the writing of existentialist theologians such as Paul Tillich and Martin Buber.

[23] Daly's work continues to influence feminism and feminist theology,[citation needed] as well as the developing concept of biophilia as an alternative and challenge to social necrophilia.

[citation needed] Daly was a member of the advisory board of Feminists For Animal Rights, a group which is now defunct.

[25] According to Lucy Sargisson, "Daly seeks in Gyn/Ecology (1987) a true, wild, Woman's self, which she perceives to be dormant in women, temporarily pacified by patriarchal systems of domination.

"[26] Audre Lorde expressed concern over Gyn/Ecology in an open letter, citing homogenizing tendencies, and a refusal to acknowledge the "herstory and myth" of women of color.

[38] Julie Kubala states that Gyn/Ecology’s “essentialist conception of gender is explicitly transphobic and implicitly racist.”[39] Wanda Warren Berry, Purushottama Bilimoria, Debra Campbell, Molly Dragiewicz, Marilyn Frye, Frances Gray, Hayes Hampton, Sarah Lucia Hoagland, Amber L. Katherine, AnaLouise Keating, Anne-Marrie Korte, Maria Lugones, Geraldine Moane, Sheilagh A. Mogford, Renuka Sharma, Laurel C. Schneider, and Marja Suhonen published their considered analyses of Daly's works and philosophy in Feminist Interpretations of Mary Daly, Penn State University Press, 2000.

She repudiated the Christian faith and regarded organized religion as inherently oppressive toward women by the time she wrote Beyond God and Father,[41][42] stating that "woman's asking for equality in the church would be comparable to a black person's demanding equality in the Ku Klux Klan".

Daly eventually gave up on theology, believing it to be hopelessly patriarchal, and she turned her efforts towards philosophical feminism.

[47][48] Daly's argument was that the equality framework serves to distract women from the radical goal of altering or abolishing patriarchy as a whole, directing them instead towards gaining reforms within the existing system.

"[55] Later in the interview when asked about her opinion on Sally Miller Gearhart's proposal that "the proportion of men must be reduced to and maintained at approximately 10% of the human race", she said, "I think it's not a bad idea at all.

[60] Mary Daly's book, The Church and the Second Sex, was translated by Helen Hye-Sook Hwang in Korean and published by Women's News Press in 1997.