U.D.O. is a German heavy metal band founded in Solingen in 1987. In their first stage (1987-1992), four studio albums were released which allowed them to gain a positive reputation in Europe. After four years of separation, in which Udo reunited with Accept, finally in 1996 the band reformed with other musicians including Stefan Kaufmann and Fitty Wienhold. Since then they have released several albums, with which they have achieved relative commercial success in some European countries such as Germany, Sweden and Russia, mainly.