Alliance Girls High School sits on 71 acres of land in Kiambu County, originally donated by the Presbyterian Church of East Africa.

She also served on the 1976 Gachathi Report committee which recommended that the Kenyan government adopt policies which would increase women's participation not only in higher education but also in science and other male-dominated spheres in the country.

[2] The first 10 girls admitted to the school arrived on 28 February 1948 and came from all the different provinces in Kenya as is still the case today.

The school also participates in the national quota system that sees a balance in admission of students from all Kenyan Districts.

[9][10] The school's crest is composed of a white torch yellow flame superimposed over St. Andrew's Cross on a green background.

The initials AGHS are above the crest, while the school motto "Walk in the light" is beneath it, both written in yellow.