Helmuth Keller studied German language and obtained his Master Degree at the University of Cologne. Since 1988 he gives instruction in German language at NGO's, at public schools and privately as well for students from all over the world.

Among his employers one can find different industries, as for example: telecommunications, financial services, theatre, catering trade, music production and other ones.

Helmuth Keller developed a new software for German as a foreign language. This software was already a great help for many students.