Guy Bernard Maddison is an Australian punk and grunge musician. From 1986 to 1989 he worked as a member of noise rock group Lubricated Goat and appeared on their album Paddock of Love. He was a member of Bloodloss (1993–1997), a blues-punk band, alongside Mark Arm on vocals. From 2001 Maddison is the bass guitarist of the United States–based grunge band, Mudhoney, and has worked on their studio albums, Since We've Become Translucent (2002), Under a Billion Suns (2006), The Lucky Ones (2008), Vanishing Point (2013), Digital Garbage (2018) and Plastic Eternity (2023).