"Sussudio" is a pop song by Phil Collins, released as a single in February 1985. The song is also the first track on Collins' third album, No Jacket Required,released in January of the same year. The song entered frequent rotation on MTV in May, and by July 6, both the single and the album reached number one on their respective U.S. Billboard charts. The music video, which was filmed in a pub owned by Richard Branson, featured Collins playing the song to a crowd that is bored at first, but gets excited and starts dancing when Collins begins performing.

The main lyric came about as Collins was improvising lyrics to a drum machine track he had programmed: "suss-sussudio" was a working wording that scanned properly. After trying to find an alternative word to fit the rhythm, the singer decided to keep "Sussudio" as the song title and lyric. The song is about a normal crush that a schoolboy may have on a girl and that by saying "suss-sussudio" may raise speculations about the boy having a stutter. The song was received mostly positively, and has been mentioned in numerous moments in pop culture.

Collins has said that he "improvised" the lyric. Collins was just playing around with a drum machine, and the lyric "sus-sussudio" was what came out of his mouth. "So I kinda knew I had to find something else for that word, then I went back and tried to find another word that scanned as well as "sussudio", and I couldn't find one, so I went back to "sussudio"," Collins said. According to Collins, the lyrics are about a schoolboy crush on a girl at school. Collins' older daughter has a horse named "Sussudio".

The music video for the song was filmed at a pub owned by Richard Branson in London. The accompanying music video features Collins, as well as long-time collaborators Daryl Stuermer and Chester Thompson. It begins with an outdoor shot of a pub, then cuts to Collins and his band playing for a uninterested crowd. The crowd slowly migrates toward the band as the song progresses, leaving them cheering at the end. Renowned bass player Lee Sklar also appears in the video, however neither Sklar nor Thompson played on the actual studio recording.

Reception for the song was mostly positive. Keegan Hamilton of the Riverfront Timessaid that the song was the best track on the album, saying that it's "catchy gibberish." "Even though this song isn't on the Flashdance soundtrack, it makes me want to put on some goofy legwarmers and kick out an aerobics routine. Where the vast majority of artists from this era try out the synthesizer/keyboard/horn section soup and fail miserably, Collins seems to have the recipe down to a science," Hamilton adds. However, Geoff Orens of Allmusic believes that the song is "dated." Robert Hilburn of The Los Angeles Timesthought the song had a "friskier R&B style" as compared to Collins' other songs, and agreed that it sounded very much like a Prince song.

Michael R. Smith of The Daily Vaultbelieved that "Sussudio" was the best track on the album, calling it a "monster track," also adding that "This is a song that chugs and churns along at a gingerly pace, set to a beat that is sure to get car speakers thumping. At the time, it was like nothing you had ever heard before on the radio. The word 'Sussudio' may not have meant anything, but the song itself was pure magic." David Fricke of Rolling Stonewas not a fan, saying that songs like "Sussudio", with the heavy use of a horn section, were "beginning to wear thin."

It is one of Collins' more famous songs and is referenced in many different media, including books, stand-up comedy acts and television shows. Collins has said that this is the song people most often sing to him when they spot him on the street.. The protagonist of the novel and film adaption of American Psycho, Patrick Bateman, briefly discusses the song, before engaging in sexual intercourse with two prostitutes while it plays loudly from his CD player in the background, amongst other work by Phil Collins. It was heavily criticized for sounding too much like Prince's song "1999", a claim which Collins does not deny, saying that he is a big fan of Prince's work.

"Sussudio" was the first track released as a single in the UK, and the second to be released in the US. In the UK the song reached number 12 on the UK charts. In the US, the song entered frequent rotation on MTV in May, and by 6 July, both the single and the album had reached number one on their respective US Billboard charts. A remix of the song appeared on Collins' 12"ersalbum.