When the Union of South Africa was formed in 1910, the electoral qualifications in use in each pre-existing colony were kept in place.

The first challenge to the Cape Qualified Franchise came with the Women's Enfranchisement Act, 1930 and the Franchise Laws Amendment Act, 1931, which extended the vote to women and removed property qualifications for the white population only – non-white voters remained subject to the earlier restrictions.

In 1936, the Representation of Natives Act removed all black voters from the common electoral roll and introduced three "Native Representative Members", white MPs elected by the black voters of the province and meant to represent their interests in particular.

It covered largely the same area in 1994 as it had on its formation, stretching from Mutual railway station in the north, across the Black River and on to most of eastern Rondebosch and Wyndover.

He would hold it until 1986, when he resigned alongside PFP leader Frederik van Zyl Slabbert, to fight apartheid from outside parliamentary politics, and later became deputy chairman of the Truth and Reconciliation Commission.