[3][4] Her mother, Wangari Maathai, was a social, environmental and political activist and the first African woman to win the Nobel Peace Prize, in 2004.

After completing high school, she moved to Geneva, New York, to attend Hobart and William Smith Colleges, where she majored in biology and graduated in 1994.

[13] Mathai serves on the World Future Council and on the board of the Green Belt Movement (GBM),[14] which was founded by Wanjira's mother Wangari in 1977.

[21] Mathai serves on the advisory board of the Clean Cooking Alliance, and is also a member of the Earth Chapter International Council.

[7][26][27] The foundation looks to advance the legacy of Wangari Maathai by promoting a culture of purpose with young people serving as leaders.

[16] As an illustration of her faith in the importance of educating youth, she was the project director for the Wangari Maathai Institute for Peace and Environmental Studies at the University of Nairobi (WMI).

[2][32] As of December 2019, Mathai has served as Vice President and Regional Director for Africa at World Resources Institute.

[14][1] In this capacity, Mathai convinced the Kenyan Environment Minister Judi Wakhungu to commit to restoring 12.6 million acres of deforested land in Kenya by 2030, building on her mother's environmental activism legacy.