Würzburg to Palestine in 1935. Sommer moved to New York at the age of 24 to work for Q1 Corp., a small computer company that was taken over in 1974 by the German Nixdorf Computer AG. After a brief stopover in Germany, he became head of the Nixdorf branch in Paris for two years in 1977, later heading overseas. In 1980 Sommer moved to the Japanese Sony Group, where ten years later he became the executive chair in the United States and in 1993 President and COO of Sony Europe. In the perior 1995-2002 Chairman of the Management Board, Deutsche Telekom AG; 2004- 2009 Member of the Board of Directors, Motorola Inc., USA; 2009-2011 First vice president, Head ofthe Telecom Assets Business Unit of Sistema. From May 2004 to December 31, 2006, he was a member of the supervisory board of the former German chemical company Celanese. Since July 2004 Sommer has been a member of the board of directors of the US group Motorola. Since May 2003, he has been Chairman of the International Advisory Council of the Russian Sistema Group. As a consultant, Sommer is closely associated with the investment firm The Blackstone Group LP, which holds interests in Celanese and Deutsche Telekom. Since September 2006, Sommer has been a member of the board of directors of the Indian company Tata Consultancy Services.