Zille is a former journalist and anti-apartheid activist and was one of the journalists who exposed the cover-up around the death of Black Consciousness leader Steve Biko while working for the "Rand Daily Mail" in the late 1970s. She also worked with the Black Sash and other pro-democracy groups during the 1980s. In the political arena, Zille has served in all three tiers of government, as the Western Cape's education MEC (1999–2001), as a Member of Parliament (2004–2006), as Mayor of Cape Town (2006–2009), and as Premier of the Western Cape (2009–2019).