She became best known as Sarah Jane Smith in the British television series Doctor Who, appearing as a regular cast member from 1973 to 1976, alongside both Jon Pertwee and Tom Baker, and reprising the role many times in subsequent decades, both on Doctor Who and its spin-offs, K-9 and Company (1981) and The Sarah Jane Adventures (2007–2011).

Sladen returned to the public eye in the 2000s with more Doctor Who related appearances, which culminated in taking a regular lead role in The Sarah Jane Adventures.

She also made regular guest appearances on the main television series and provided voice-over commentaries and interviews for its releases to DVD.

[7] After two years at drama school, Sladen began work at the Liverpool Playhouse repertory company as an assistant stage manager.

[2] However, she was scolded for giggling on stage due to her future husband Brian Miller whispering the words "Respiration nil, Aston Villa two" in her ear while he was playing a doctor.

[8] Sladen was such a good assistant stage manager that she did not get many acting roles, a problem that was solved when she accidentally made a mistake on one occasion.

She also got the occasional part on Radio Leeds and Granada Television, eventually appearing as barmaid Anita Reynolds in 1970 in six episodes of the long-running soap opera Coronation Street.

She declined but accepted his second offer of a pilot for a spin-off series called K-9 and Company, co-starring K-9, the robot dog from Doctor Who.

[21] She reprised the role in the 1993 Children in Need special Dimensions in Time, and in the 1995 independently produced video Downtime alongside former co-star Nicholas Courtney as Brigadier Lethbridge-Stewart and Deborah Watling as Victoria Waterfield.

[22] Big Finish Productions produced two series of Sarah Jane Smith audio adventures set in the present day, released in 2002 and 2006.

Sladen worked a lot of the characterisation herself—in the lead-up to the broadcast of "School Reunion" she was quoted in the Daily Mirror as saying: "Sarah Jane used to be a bit of a cardboard cut-out.

[25] Sladen also read original audio stories on CD for The Sarah Jane Adventures,[14] which were released in November 2007: The Glittering Storm and The Thirteenth Stone.

Subsequent appearances include a two-year stint as a presenter for the children's programme Stepping Stones, a lead role with Miller playing her husband in ITV drama Send in the Girls, a BBC Play for Today, a role as a stand-up comic's spouse in Take My Wife, and a small part in the film Silver Dream Racer as a bank secretary in 1980, only her second film appearance.

[31] In 1981, former Doctor Who producer Barry Letts cast her as the female lead in the BBC Classics production of Gulliver in Lilliput.

[32] After the birth of her daughter Sadie in 1985, Sladen went into semi-retirement, placing her family first, but found time for the occasional television appearance.

Following the audio production of The Paradise of Death in 1993, Sladen restarted her regular public appearances in the United Kingdom.

In 1996, she played Sophie in Faith in the Future, and appeared in 15 episodes of the BBC schools programme Numbertime, which was repeated annually for around ten years.

In 2008 and 2009, Sladen appeared in a pantomime production of Peter Pan at the Theatre Royal Windsor, playing Mrs.

[34] Sladen's last fan event was at the British Film Institute on 12 October 2010, where there was a special showing of The Death of the Doctor, followed by a Q&A session.

The BBC released an audio CD version of the book, read by fellow Doctor Who alumna Caroline John, on 1 December 2011.

[39] Sladen was diagnosed with pancreatic cancer in February 2011 and died on 19 April 2011;[40][41] she had previously fought the disease in 1999.