Although she has made many appearances on both screen and stage, Manning is best known for her part as the companion Jo Grant in the BBC science fiction television series Doctor Who.

Manning was severely myopic, but teachers failed to understand her condition and she was teased by the other children for having poor eyesight and wearing large glasses.

Manning was thrown through the windscreen and through a plate glass window ending up on the bonnet of the car, leaving her back and both her legs broken and her face disfigured.

Inspired by this, upon her return to the UK, Manning trained at the Webber Douglas Academy of Dramatic Art,[8] and then joined a Wolverhampton repertory company.

She struck up an immediate rapport with her co-stars Pertwee, Nicholas Courtney (The Brigadier), John Levene (Sergeant Benton), Richard Franklin (Captain Mike Yates) and Roger Delgado (the Master).

Making her debut in the episode Terror of the Autons, the character of Jo Grant instantly became liked by audiences to the extent that she is often thought of as the archetypal companion along with Sarah Jane Smith and Rose Tyler.

"[5] Patrick Mulkern of the Radio Times said of her portrayal that "she had it all: innocence and gumption, courage and a terrific scream, an irresistible bubbly mixture of tomboy and sexpot.

[10] Manning had a particularly close relationship with Pertwee to the extent that he would pick her up every day from outside her house, either in his car or on his motorbike where she would ride pillion, and take her for filming or rehearsals for Doctor Who.

Pertwee was reportedly very sad at her departure due to their close working relationship and cited Manning leaving and the death of Delgado as two major reasons why he left the show a year later.

[16] Straight after leaving Doctor Who in 1973, Manning presented her own ten-part TV series for the BBC on crafts, entitled Serendipity shown in the daytime schedules.

Manning followed this with a role in the comedy film Eskimo Nell (1975) as Rosalind Knight's rebellious daughter before she was reunited with Jon Pertwee when she appeared in Whodunnit?

[citation needed] Manning wrote a comedy pilot entitled Two in the Bush in 1986 with her friend and fellow actress Penelope Whiteley.

[23][24] Manning was also offered a role in popular Australian soap Home and Away but she had to turn it down due to busy work commitments.

[citation needed] Some time between 1994 and 1996, Manning moved to live in Los Angeles where she shared a flat with her best friend Liza Minnelli[26] and had large house parties that had guests including Sean Penn, Shirley MacLaine and Whoopi Goldberg.

[27] Not a Well Woman's opening performance was in New York and Minnelli invited some top producers to watch the premiere including Blake Edwards.

which is shown in a day-by-day format showing her time attending various fan conventions on a trip to the U.K.[28] Manning was the voice of Australia's UKTV television channel in the late 1990s and provided voiceovers for the indents.

She also hosted her own chat show from 2001 until 2008 called Preview with Katy Manning and had guests including Lenny Henry, Edgar Wright, Petula Clark and Basil Brush.

In 2002, Manning appeared in an episode of All Saints and also starred in a production of the Ray Cooney play It Runs in the Family with Robert Coleby and Judy Cornwell.

[29] In 2003, Manning directed the original run of the musical play Eureka as well as other productions including Banjo Paterson and Shirley Valentine.

alongside Gorden Kaye as René Artois at Twelfth Night Theatre in Brisbane as original actress Vicki Michelle was unavailable.

[33] It toured through March and April in England and also played at the 2009 Edinburgh Fringe at The Gilded Balloon Wine Bar in August.

In 2011, Manning appeared as Blodwyn Morgan, a Welsh busybody and clairvoyant, in the touring stage play Death by Fatal Murder.

[37] In 2019, 2020 and 2023, Manning reprised her role of Jo Jones for three specially filmed scenes to promote three Doctor Who blu-ray box sets for her three seasons on the programme.

[38] She also starred in a special episode to mark the conclusion of The Sarah Jane Adventures, released via YouTube in 2020 on the anniversary of Elisabeth Sladen's death.

Manning once told of how she was dropped off for her first day at drama school in a black Cadillac with her boyfriend Bardens and his Shotgun Express bandmates including Stewart.

Still frail as toddlers, they continued to suffer from severe health issues, including from whooping cough which made their immune systems collapse.