"I'm a Believer" is a song written by Neil Diamond and recorded by the Monkees in 1966 with the lead vocals by Micky Dolenz.
The single, produced by Jeff Barry, hit the number-one spot on the U.S. Billboard Hot 100 chart for the week ending December 31, 1966, and remained there for seven weeks, becoming the last No. 1 hit of 1966 and the biggest-selling single for all of 1967. Billboard ranked the record as the No. 5 song for 1967.
While originally published by Screen Gems-Columbia Music (BMI), it is now published by Stonebridge Music/EMI Foray Music (SESAC), with administration passed to Sony/ATV Music Publishing and Universal Music Publishing Group.
The song was No. 1 in the UK Singles Chart for four weeks in January and February 1967 and reached the top spot in numerous countries, including Australia, New Zealand, Canada, and Ireland.
Billboard described the song as 'an easy-go dance mover' that 'will hit with immediate impact'. Cash Box said the single is a "medium-paced rocker [that] is full of the group's top notch harmonies and is laced with infectious sounds."
The song appeared in four consecutive episodes of the television series The Monkees in December 1966. The Monkees principals later played it for themselves in live appearances, on overseas tours, and at reunion concerts.