20 Years of Jethro Tull is a 1988 boxed set which spans the first twenty years of Jethro Tull. It was issued as five LPs: Radio Archives, Rare Tracks, Flawed Gems, Other Sides of Tull, and The Essential Tull. It was simultaneously released as both a three CDs and a three-cassette set, titled 20 Years of Jethro Tull: The Definitive Collection. All three versions were housed in a 12x12 inch cardboard-box, with 24-page booklet, the CD and cassette versions having a black plastic tray. A single CD sampler and a double LP album were also created, titled 20 Years of Jethro Tull: Highlights.