Barber was born in Durban, Union of South Africa, the daughter of Heather Maureen (née Robb) and Frederick Werndly Barry van der Riet.

In 2006, she joined the cast of ITV soap, Emmerdale, playing the character of DCI Grace Barraclough, investigating the death of Tom King on Christmas Day.

In 2009, she appeared as hospital administrator Jean McAteer in The Royal, another ITV drama series set in Yorkshire.

[8] Her stage work has included Macbeth, Killing Time with Dennis Waterman, High Flyers with Hugh Grant, Make Me a Match and The Graduate.

In 2011, Barber starred alongside Christopher Timothy and Denis Lill in Alan Ayckbourn's Seasons Greetings, playing Belinda.

In 1989, she appeared as Elisabeth Jekyll in Edge of Sanity, and the 1997 film Déjà Vu alongside Vanessa Redgrave.

Glynis van der Riet married actor Paul Antony-Barber, whom she met at drama school, in 1977;[9] the couple divorced in 1979.