Parents Music Resource Center.
Headed and started by Tipper Gore in 1985, when she heard her then 5 year old daughter listening to Prince´s "Darling Nikki" on the Purple Rain b-side.
The "most representative and most youth endangering" musicians were invited to Congress: Dee Snider (Twisted Sister, okay, they´d been rude back then), Frank Zappa (sang explicit lyrics too) and - lo and behold - John Denver who sang "Country Roads".
The whole thing turned into hysteria as more and more desperate housewives attended the movement and even started to cencore songbooks in kindergardens.
The final decision was to mark youth endangering records with the following stickers:
A = music that promoted alcohol abuse
S = satanic lyrics
V = music that supports violence lyrically
Later on they used that comprehensive sticker "Parental Advisory - Explicit Lyrics".
PMRC lead by Tipper Gore
"Tipper lead the war against the record industry,
she said she saw the devil on her MTV"
(Cinderella "Shelter Me")