From 1975 to 1977 he led the group Clarinet Contrast, consisting only of clarinets, with Perry Robinson, Hans Kumpf, Bernd Konrad and Michel Pilz. At the end of the 1970s he was leader of one of West Germany's best-known jazz groups. At the beginning of the 1980s he took part in a Clarinet Summit (which was created by Joachim E. Berendt and himself) with John Carter, Perry Robinson, Gianluigi Trovesi and others. Since those days Jörgensmann has been involved in numerous international projects. In 1985 Jörgensmann toured Europe with bassist Barre Phillips and reed player Paul McCandless. He was a member of Willem van Manen's "Contraband" (1985–1998), Andrea Centazzo's "Mitteleuropa Orchestra" (1983–1985), John Fischer's "Interface" (1981–1996) and Franz Koglmann's "Pipetet" (1983–1985). At the same time he was also leader of "Klarinettenquartett Cl-4" and co-founder of large ensemble "Grubenklangorchester". In 1987 Jörgensmann was the subject of a documentary film, "Theo Jörgensmann, Bottrop, Klarinette", directed by Christoph Hübner.