"What a Fool Believes" is a song written by Michael McDonald and Kenny Loggins. The best-known version is the recording by The Doobie Brothers (with McDonald singing lead vocals) for their 1978 album Minute by Minute. Debuting at number 73 on January 20, 1979, the single reached number one on the US Billboard Hot 100 on April 14, 1979 for one week. The song received Grammy Awards in 1980 for both Song of the Year and Record of the Year. .