Girls Under Glass (GUG) is a musical group from Hamburg, Germany, founded in 1986 by Thomas Lücke, Hauke Harms, and Volker "Zaphor" Zacharias. Described as "an indispensable part of the German wave and gothic scene", GUG began as a gothic rock band, but quickly crossed genre boundaries, incorporating metal and electronic music of various kinds. They have generally been classified as a darkwave act, but have ranged across the goth–industrial "dark music" spectrum, including into industro-metal, and their work has integrated elements of pop, techno, and trip hop. Grenzwellen-News wrote of the band, "Even after 20 years, it is almost impossible to define and pin-down Girls Under Glass stylistically." A review in 2001 concluded that "even in its most experimental phases, the band has never lost its identity".
Axel Ermes joined in 1989, and Lücke left the next year, but rejoined in 2016; Harms retired in 2017. The band's lyrical material is sometimes in German, sometimes English, or a mixture of both on some tracks. Trauma, a Zaphor and Harms side project, is primarily trance with new age influences, and Traum-B (Harms and Ermes) produced Goa trance and psy-trance. GUG formed as a replacement for an earlier gothic–wave band, Calling Dead Red Roses, which formed in 1985, produced one album, then splintered.