This paper uses an unbalanced panel data set for exporting firms from manufacturing industries in one German Federal state, Lower Saxony, to investigate the microstructure of the recent export boom. Looking at data for 1995/96 - 2001/2002 it is demonstrated that a considerable number of plants start and stop exporting in each year, but that most of the export dynamics is due to positive and negative changes of exports in plants that continue exporting. A small fraction made of 4 - 5 percent of all exporting plants is responsible for around 70 to 80 percent of the gross increase in exports...