"Part-Time Lover" is a song by American R&B singer and songwriter Stevie Wonder, released as the first single from his twentieth studio album, In Square Circle (1985). The song reached number one on the Billboard Hot 100, R&B, dance, and adult contemporary charts, becoming Wonder's final number one hit to date. The song's simultaneous chart successes made Wonder the first artist to score a number-one hit on four different Billboard charts. The song was also released as a special 12" version. Lyrically, it tells the story of a man who is cheating on his wife with a mistress, only to find out in the end that his wife is cheating on him as well.