"Borderline" is a song by American singer Madonna from her 1983 self-titled debut studio album. It was released on February 15, 1984, by Sire Records as the album's fifth single and, years later, was also included on the singer's greatest hits albums The Immaculate Collection (1990) and Celebration (2009). Written and composed by its producer Reggie Lucas, the song was remixed by Madonna's then-boyfriend John "Jellybean" Benitez. Lyrically, the track talks about an unfulfilled love and finds the singer using refined and expressive vocals.
It received critical acclaim; contemporary critics and authors called it the most harmonically complex track from Madonna, and lauded the singer's vocals. In the United States, "Borderline" became Madonna's first top-ten hit on the Billboard Hot 100, peaking at number ten in June 1984. In the United Kingdom, it peaked at number two after it was re-released as a single in 1986. The song reached the top 10 or 20 in numerous European nations, while topping the singles chart of Ireland.
The accompanying music video portrayed Madonna as the girlfriend of a Hispanic man, to whom she returns after being enticed to pose and model for a white photographer. It generated academic interest for its use of power as symbolism. According to some critics, the video helped establish Madonna's early success, and she was credited for resisting the taboo of interracial relationships within it. Madonna performed the song in two of her concert tours: Virgin (1985) and Sticky & Sweet (2008); it has been covered by artists such as Duffy, Jody Watley, Counting Crows and The Flaming Lips.