In 1959 he obtained his engineering degree from the Dortmund University of Applied Sciences and Arts.
[3] In 1959 Pannenbaecker started his career at Siemens in planning and cost accounting for the construction of industrial plants in Germany and abroad.
From 1969 to 1981 he founded and directed a project management office at Kraftwerk Union, a daughter company of Siemens and AEG.
In 1981 he started his own firm for systems engineering and process management, which he directed until his retirement in 2001.
[3] From 1994 to 1996 Pannenbaecker was president of the International Project Management Association as successor of the Danish Morten Fangel, and was succeeded by Gilles Caupin from France.