"(You Don't Know) How Glad I Am" is a song written by Jimmy Williams and Larry Harrison. Its best-known recorded version is by Nancy Wilson, which was a hit single in the summer of 1964, when it reached number 11 in the USA. In April 1965 "...How Glad I Am" received the Grammy Award for Best Rhythm & Blues Recording: Wilson was reportedly surprised by the categorization of "...How Glad I Am" as R&B as she considered the track to be a pop record.

Kiki Dee recorded "(You Don't Know) How Glad I Am" in 1964 with an arrangement - by Les Reed - based on the Nancy Wilson recording: Dee then remade the song as "How Glad I Am" in 1975 with an uptempo bluesy arrangement, and this version - produced by Gus Dudgeon and credited to the Kiki Dee Band - was issued that spring as the follow-up to "I've Got the Music in Me" reaching number 33 UK and number 74 US. The Kiki Dee band version also charted in the Netherlands (number 16) and Flemish Belgium (number 30)

"(You Don't Know) How Glad I Am" has also been recorded by Bonnie Bramlett, Ellen Foley, Maria McKee, and - as "How Glad I Am" - by Fontella Bass, Joyce Cobb, Aretha Franklin, The Greyboy Allstars, Brenda Lee, Olivia Newton-John and Sandie Shaw.

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