Sisters of Mercy made the first foundation in Kenya in 1956.

In the 1960s through the early 1980s, Sisters of Mercy established and ran health and educational facilities. Many of these institutions have been transferred to government ownership with the community or diocese retaining some sponsorship responsibilities.

From the 1990s on, the Sisters of Mercy have directed much energy to ministering in city slums the development of which resulted from migration to the cities in times of drought, famine and strife. The physical conditions which millions of these displaced people face are dire, and most lack water, sanitation, roads and electricity.

The responses of Sisters of Mercy in the slums have included a focus on providing primary education and sponsoring students to further education and skills training in order to break the cycle of poverty. Some Sisters of Mercy work in health clinics where they treat many who come with diseases that are a result of the lack of clean water and poor sanitation.

It is estimated that one in four people in Kenya are infected with HIV/AIDS. The Sisters of Mercy address the care, nutrition, education, and health needs of many children who have been left orphaned as a result of the HIV/AIDS pandemic and also run programmes to help people make choices that will lessen the spread of the disease.

Additional ministries of Sisters of Mercy in Kenya include the visitation of prisoners and accompanying refugees and other displaced persons.