Rogue Traders is a BBC One investigative/undercover consumer affairs television programme starring Matt Allwright, an investigative journalist, and Dan Penteado, a private investigator and Allwright's co-host. The show focuses on investigating and exposing the dubious work practices of tradespeople and businesses who have received complaints against them from their customers, often through the use of hidden cameras and rigged situations, sometimes sending members of the show's research team undercover to secretly record any training methods taught to a business' employees that is suspicious or unethical.

The programme ran for nine series between 2001 and 2009, before it was decided to incorporate Rogue Traders' format as a multi-part segment for the long-running consumer series Watchdog; the segment retained the show's name after its merger in 2009. In 2012, Penteado was removed from the show, after he was jailed for benefit fraud.

For each episode of Rogue Traders, Allwright seeks to expose individuals who have come to the attention of the research team, usually for one or several reasons, including being unethical with sales, aggressively pursuing a customer for money, creating unnecessary work, selling something that is not wanted, or committing a criminal offence/breaking the law during a job. Such individuals are usually found through customers writing to the programme outside of filming/broadcast, who were unsatisfied by the individual's work, behaviour or sales techniques, made complaints against them that they refused to deal with, or felt cheated by the amount they paid out, whereupon the programme's researchers will investigate the trader further. While the show usually has an improvised and humorous feel to each episode, per the script created by Allwright, the consumer investigative nature of the programme ensures that each trader's dubious nature is looked into seriously. In addition, the show often pursues a trader to acquire evidence that supports the complaints their customers make, to which the show uses an occasional catchphrase – "We never give up."

The general format of each episode is that Allwright will usually introduce viewers to the rogue trader(s) they are seeking to expose, revealing brief details about the issues they have caused, and highlighting the business that they run; for the latter, the show has generated a catchphrase, in which the host occasionally advises viewers that the business is "not to be confused with any other companies of the same name" or any other variation of it. He will then meet with the trader's customers who complained about them and wrote to the programme's research team with their experiences, through which Allwright will usually ask them what the trader was like, what they did, and how the customer felt about the whole experience. In some cases, the programme is sometimes contacted by a former associate of a business the programme is investigating, who can provide an inside look at how they perform and the associate's thoughts on such behaviour.

After hearing enough about the trader, the next step focuses on filming the rogue trader in the act. How this is done varies, depending on the work that the rogue trader is involved in, but in all cases, hidden cameras are used to record everything, while either a trade or legal expert is brought in to view the recorded footage and provide their opinions, thoughts and criticism over what they see being done, including if they suspect a trader is lying to a customer about something that is untrue, questioning what a trader is doing on a job, revealing what something should really cost that a trader is overpricing, and if a trader is doing something illegal that they shouldn't be doing. The following lists how certain types of traders are filmed secretly to provide evidence of dubious work practices:

In all cases, once enough evidence of a trader's practices, ethics, and other misdemeanors are acquired via hidden cameras, Allwright will make arrangements to interview the trader and question them on what they do, and why they behave in a way that can leave customers cheated, unhappy, and shocked. In some cases, if the trader had appeared in an earlier episode for similar behaviour, the host will also question them on why they are still trading in the same manner as before. How the host arranges the interview, is done in one of two ways – for DIY traders, Allwright will usually set up a sting, in which the trader is called out to deal with a job, only to be ambushed by the host, who during the fourth and fifth series, wore a disguise and did not break character until after a suitable amount of time passed. For most others, Allwright will usually visit the place they work from and attempt to interview them there. In most cases, the trader(s) will avoid answering questions, sometimes swearing, locking themselves away in a place they cannot be reached by the host, or trying to give vague, unrelated answers while walking/driving away. In some cases, Allwright manages to interview them before they leave or he and his camera crew are asked to leave. In rare cases, traders may aggressively force the host and his camera team to leave, even intimidating them with the support of close friends.

An episode then ends with Allwright warning customers about trading with the rogue trader, whereupon he narrates a response to viewers, made by the trader in relation to the show's investigations and the allegations of their practices, actions and attitude to customers.

For some episodes, usually the last in the series, the show looks back at some of the traders they featured and reveals what happened to them after the episode they featured in had ended. In these episodes, footage from a trader's episode is used to remind viewers of how they performed and the opinions of their customers who complained about them and the experts who observed their work practices. New footage is then shown of what occurred afterwards with the trader, which include interviews with customers who had dealings with the trader and who decided to come forth on to the programme about their experience, and with investigators (mainly from Trading Standards) who investigated the trader, and found enough evidence to prosecute them for unethical, aggressive and illegal business conduct. For the latter, where the trader's trial took place, is mentioned by the host, who also states the sentence the trader received.