[2] She started her long career in the consumer oil sector in 1993, working as an Export Manager for Agip Kenya Limited (AGKL), responsible for downstream distribution of fuels and oils from the depot in Mombasa to five countries in the African Great Lakes area, serving in that capacity until 1998.
[2] In 2000, she switched companies and moved over to Shell/BP, as the LPG Manager, based in the coastal city of Malindi, serving in that capacity until 2001.
[2] In 2008, Ms Mwangi was appointed the Head of Sales & Marketing division at the National Oil Corporation of Kenya (NOCK), serving in that capacity for the next five years.
[1][3] After performing in an active capacity for one year, Mwangi was confirmed by the board of NOCK, as the substantive CEO and managing director, for a three-year term effective 1 August 2017, replacing Sumayya Hassan-Athmani, who had resigned in July 2016.
[4] In July 2016, in her capacity as Acting CEO, she joined the board of directors of NOCK, and had been a member until her departure in October 2019.