She has worked with many leading fashion photographers including Patrick Demarchelier, Steven Meisel, Steven Klein, Nick Knight, Mario Testino, David Sims, Bryan Adams, Nadav Kander and featured in magazines including Vogue, W, Elle, Harper's Bazaar, Harpers & Queen, i-D, and Visionaire.

Since 2005, she has been one of the faces of the British high-street chain Marks and Spencer and in 2008 she launched the haircare line model.me for Toni & Guy, alongside Jamelia and Helena Christensen.

[10] In 2011, O'Connor's personal assistant, Michelle Knox Brown was convicted of stealing around £12,000 from the model, which she spent on foreign holidays.

[5] O'Connor wrote and presented two documentaries on fashion, Erin's Model World and In Search of Beauty, for BBC Radio 4.

For the launch campaign, O'Connor swapped roles and stood behind the camera for the first time to photograph models holding the slogan 'Size Me Up'.

[21] O'Connor was appointed Member of the Order of the British Empire (MBE) in the 2017 Birthday Honours for services to fashion and charity.