The school is located in gatanga Location of Gatanga constituency of Muranga county 7km to the west from the thika centre. The school is a four-streamed school with a student population of 800 students drawn from central and Nairobi province. However, with effect from 2012, a fifth stream will be due to demand. The school sits on a ten-acre plot which contains the hostels, classrooms, science laboratories, staff houses (24), kitchen, school hall, computer lab and playing fields.
Gatanga girls is a provincial public school run by the catholic dioceses of Muranga , The Board of Governors in conjunction with a supportive PTA. At the school level the management is as shown above.
The administration of the school comprises of the following: Non-teaching staff, discipline committee, tender committee, staff welfare committee, academics committee, careers/ guidance & counselling and co-curricular committee. With the exception of the non-teaching staff, the others are standing committees made up of teachers.
The non-teaching staffs include the secretaries, accounts clerks, bursar, cooks, watchmen, drivers and grounds men are there, principally to perform the respective duties which are beyond the scope of the students.