Selling out is a common slang phrase. Broadly speaking, it refers to the compromising of one's integrity in exchange for money or other personal gain. It is commonly associated with attempts to increase mass appeal or acceptability to mainstream society. A person who does this is labelled a sellout.

The phrase is often heard in the musical community, where it is used to imply that an artist has compromised their artistic integrity in order to gain radio airplay or obtain a recording contract, especially with a major label, The classic example of this being when Chumbawumba signed to EMI after years of viciously attacking the organisation. Often, the label will force the style of a particular record producer on the performer, or insist on inclusion of songs by commercial songwriters. Or, the label may refuse to release an album, deeming it uncommercial, though this indicates that the artist or group maintained their standards or values.

Fans sometimes assume that any change in an artist's direction must be an attempt to appease record labels or to make more money through broader appeal. This may fail to account for natural artistic development, which may lead an artist in directions that their original fans disliked.

The accusation of selling out is often made against punk bands who sign to major labels (i.e Chumbawumba, Green Day, The Offspring), since punk has a cultural tradition of independence and doing it yourself. Similarly, it is often heard in the indie rock and metal communities, which like punk have a tradition of mainstream rejection and/or anticonsumerism. Metallica is perhaps metal's most famous supposed sellout. On the other hand, Metallica brought metal to the mass audience. Similarly, Bob Dylan outraged folk music purists by, in their view, selling out their favorite music for rock and roll. However, Dylan has changed direction repeatedly throughout his career.

It should be noted that many people see nothing wrong with tailoring a product to the tastes of its audience, or with taking practical and financial considerations into account when making art. And, in regard to theater shows, musicals, etc, a "sell out" show is simply a show so successful that all tickets are sold out, and is considered a big compliment. Selling out may be then gaining success at the cost of credibility.

Many songs have been written about selling out, including:

• "Hooker with a Penis" by Tool
• "Sell Out" by Reel Big Fish
• "Johnny Quest Thinks We're Sellouts" by Less Than Jake
• "Never Sell Out" by The Exploited

These song range in approach to the term "selling out"; from declarations that the band will never sell out, to aggressive messages towards fans accusing bands of "selling out".

The Who Sell Out is an album by The Who with mock endorsement advertisements on the cover. The album pretends to represent a radio station that plays nothing but Who music, including mock commercials and radio-station promotions. The Who became very prolific at selling their work by the end of the 1990's including 'Love Reign O'er Me' for 7-Up, 'Bargain' for Nissan, 'Overture' for Claritin, 'Happy Jack' for Hummer, 'Baba O'Riley' for Hewlett Packard, and 'I Can See for Miles' for Sylvania Silverstar headlights.

Some music lovers feel that another example of selling out is when a band or artist allows their music, once it has been proven to be successful in the marketplace, to be sold to a company for use in commercial advertising. Some well-known examples of this practice are listed below with the company sponsor, in parentheses, after the artist and title of the song sold:

• Rolling Stones 'Start Me Up' (Microsoft)
• Led Zeppelin 'Rock and Roll' (Cadillac)
• Aerosmith 'Dream On' (Buick)
• Beatles 'Revolution' (Nike)
• Clash 'Should I Stay or Should I Go' (Pontiac)
• Ramones 'Blitzkrieg Bop' (AT&T)
• New Order 'Blue Monday' (Sunkist)
• Madness 'It Must be Love' (Snack Pack Pudding)
• Sting 'Desert Rose' (Jaguar)
• Barenaked Ladies 'One Week' (Mitsubishi)
• Madonna 'Ray of Light' (Microsoft)
• Styx 'Mr. Roboto' (Volkswagon)
• David Bowie 'Rebel, Rebel' (XM Radio)
• Bob Dylan 'Love Sick' (Victoria's Secret)
• Verve 'Bitter Sweet Symphony' (Nike)
• Fatboy Slim 'Praise You' (Mercedes)
• The Smiths 'How Soon is Now' (Nissan)
• Moby 'Porcelin' (Bailey's Irish Creme)
• Lenny Kravitz 'Fly Away' (Nissan)
• Pete Townsend 'My Love Open the Door' (JC Penny)
• Rick James 'Give it to Me Baby' (Papa John's Pizza)
• Queen 'I Want to Break Free' (Coke - C2, Ban - Deoderant)
• Squeeze 'Tempted' (Trident Gum)
• Friggs 'Bad Word for a Good Thing' (Chevrolet - Trailblazer)
• U2 'Vertigo' (Apple Computer - iPod)
• Eric Clapton 'Layla' (SBC)