[1] After leaving school, Riding worked at Chichester Festival Theatre for a season, playing Anne Page in The Merry Wives of Windsor and Dorothy in The Wizard of Oz.
[3] In 1993, Riding played the role of Julie Jordan in Nicholas Hytner's Royal National Theatre revival of Carousel and won the Olivier Award for Best Actress in a Musical for her performance.
[4] In 1995 she played Anne Egerman in A Little Night Music opposite Judi Dench, followed by Sarah Brown in Richard Eyre's acclaimed revival of Guys and Dolls, both at the National Theatre.
On 12 May 2002 she appeared in the Richard Rodgers' Tribute Gala 'Some Enchanted Evening' at the Theatre Royal, Drury Lane, which was broadcast on BBC Four and has since been released on DVD.
Riding also portrayed Valerie Hobson in Andrew Lloyd Webber's musical Stephen Ward, and was one of few elements of the production to be praised by every major critic.
In September 2016 it was announced that Riding would take the leading role of Annie in The Girls musical written by Gary Barlow and Tim Firth to open at The Phoenix Theatre, London on 27 January 2017.