Grey Larsen, in the 150 Gems collections, has given us a most welcome follow-up to his encyclopedic volume, The Essential Guide to Irish Flute and Tin Whistle (Mel Bay Publications, 2003) and The Essential Tin Whistle Toolbox (Mel Bay Publications, 2004). The Gems feature not only meticulously-selected tunes, but represent the first major offerings that use Larsen's innovative system of notating Irish ornamentation. These books and online audio will help players gain a deeper understanding of the Irish musical tradition as well as provide new material to enhance the experience of the solo player and Irish session participant alike.