Hello! Project Shuffle Unit is an annual event in the Japanese idol group, Hello! Project that started in 2000. The idea was to shuffle up the existing Hello! Project groups and soloists (e.g. Morning Musume, Country Musume, Aya Matsuura, Melon Kinenbi, and others) into one of three groups for a season-long collaboration to see which shuffle group can sell the most singles.
2000: Color Group
Akagumi 4
Kiiro 5
Aoiro 7
2001: Party Groups
3-nin Matsuri
7-nin Matsuri
10-nin Matsuri
2002: Happiness Groups
Happy 7
Sexy 8
Odoru 11
2003: Elemental Groups
Salt5
7Air
11Water
2004: One School Group
H.P. All Stars
2005: Elegance Groups
Elegies
Sexy Otonajan
Puripuri Pink