Margaret Natalie Mensah-Williams (born 25 December 1961) is a Namibian politician, diplomat, and prominent SWAPO member. She currently serves as Namibia's ambassador to the United States. Mensah-Williams also served as councillor of Windhoek's Khomasdal North constituency from 1998 until 2019, and from this position was elected to represent Khomas Region in the National Council, the upper house of the Namibian Parliament from 2015 to 2019. In the National Council she was elected deputy chairperson in 1998, and chairperson in 2015. She resigned from all regional representative positions prior to the 2019 Namibian general election in order to contest for a seat in the National Assembly, Namibia's lower house, and subsequently became member of Parliament.