"How Can I Be Sure" is a popular song written by Felix Cavaliere and Eddie Brigati, and originally recorded by The Young Rascals on their 1967 album Groovin'. It became their fourth Top 10 hit in the United States, peaking at No. 4. This was the group's highest charted record with Eddie Brigati singing lead vocals. The song featured the sounds of an accordion in the background, as well as a trumpet, bass, piano, drums, and strings, giving the feeling of cabaret music.