Mandy Salter is a fictional character from the BBC soap opera EastEnders, played by Nicola Stapleton. Introduced on 12 March 1992 by executive producer Leonard Lewis, Mandy was portrayed as a teenage tearaway. She was featured in storylines about teenage homelessness, child abuse and recreational drug taking. Her relationship with Aidan Brosnan (Sean Maguire) was one of the prominent storylines featured in 1993. Due to the character's antagonistic behaviour, it has been suggested that Mandy was one of the most hated characters on television during her initial tenure. The character appeared in a special episode of Doctor Who in 1993, which was set in the fictional soap setting of Walford. Stapleton left the role and Mandy departed on-screen on 13 January 1994. Stapleton returned to the role for a nine-month stint on 29 August 2011, and left again on 31 May 2012.

Following Mandy's initial exit, Stapleton claimed that she was asked to reprise the role on several occasions; she turned these offers down until producer Bryan Kirkwood negotiated her comeback in 2011. After a 17-year hiatus, Mandy reappeared from 29 August 2011 and began a relationship with the long-running character, Ian Beale (Adam Woodyatt). Mandy's return storylines focused on her dysfunctional relationship with her mother Lorraine (now played by Victoria Alcock), her unconventional engagement to Ian, and her fuelling conflict with Ian's teenage daughter Lucy (Hetti Bywater). On 4 April 2012, it was announced that Stapleton would be leaving EastEnders for a second time. Mandy and Ian were not given a happy ending; their relationship dissolved and Mandy departed in the episode broadcast on 31 May 2012.

Mandy was one of several introductions to the cast of EastEnders in 1992. Executive producer Leonard Lewis took a tentative approach to introducing new characters in 1992. Most were introduced gradually, making an initial appearance and then joining the programme full-time a couple of months later. This allowed the producers and writers to create new characters and see them brought to life by the actors before committing them to a longer contract. Mandy first appeared in March 1992 as a school girl aged 15, abandoned by her mother in Pat Butcher's care. She left the series temporarily a few weeks later; in the storyline she went back to her mother's flat, but she returned by the summer of 1992 as a regular character, squatting in the soap's setting of Albert Square.

Mandy was portrayed as a troublesome teenager, with an underpinning storyline of child abuse and abandonment. Nicola Stapleton, 17 at the time, was cast in the role. During her initial stint in the soap, the character was featured in storylines about child and drug abuse, homelessness, blackmail, theft and prostitution (in the form of clipping).

In his 2005 book, Eastenders: 20 Years in Albert Square, author Rupert Smith classified Mandy as a "lost girl". He described her as "poisonous [...] the daughter of a dodgy old lush that Pat had picked up in a hostess bar, and she arrived in Walford to work out some grudge she held against the entire world." He added that "she lied, cheated and stole", suggesting that "there have been very few characters as entirely loathesome as Mandy Salter [...] The serpent in an East End eden." Author of EastEnders: Who's who?, Kate Lock, suggested that, "You wanted to feel sorry for homeless waif Mandy but her deviousness made it hard to even like her."

She has been described as a "manipulative force of nature" with a "spiteful streak". In 2011, the executive producer of EastEnders, Bryan Kirkwood, described Mandy as outrageous, uncompromising and pragmatic. He added, "although she's the result of a life on the streets, she's a survivor and isn't down on her luck. Mandy knows what to do to get by". Discussing Mandy in 2011, Stapleton said that Mandy only relies on herself and is "the sort of person who uses what she's got to get by." She described Mandy as minxy and incredibly flirty; someone who dresses skimpily and uses her body to get what she wants.

A lone character without family in the serial, Mandy was essentially homeless, and when she was unable to squat or rely on the kindness of strangers, she slept rough on the streets. This storyline came at a time when homelessness in London was a topical subject in the British media, partly due to the continued concern regarding Cardboard City, an area near Waterloo station that attracted a high proportion of homeless people who slept in cardboard boxes. Because of her involvement in this story arc, actress Nicola Stapleton became so affected by the plight of young homeless people that she joined the charity 'Countrywide', who raise money for the homeless. In January 1993 she told Inside Soap, "I have always thought the homeless situation was terrible, but through my research into playing Mandy, I have realised just how many young people it affects. I think it is really tragic that we have teenagers in this country sleeping out on the streets. And it isn't a problem that will go away. I just hope that by drawing attention to the problem in EastEnders more people will be willing to help [...] It is important that people realise that anyone can end up homeless. If you lose your flat or your job, you can end up in a downward spiral that will dump you on the streets. We can't shut our minds to this situation, because it could happen to any of us. I know how fortunate I am, and therefore I know that I am in a position to help, which is why I have got involved with the [charity]."

With regard to Mandy, Stapleton believed that, in 1993, she was her "own worst enemy" and that some of her misfortune was associated to her upsetting other characters: "Mandy is constantly rubbing people up the wrong way, and upsetting them. Of course she has had a hard life, but she doesn't do herself any favours either. I would like to see her get a break and a chance to finally make something of herself."