This paper reports new results on the role of firms from various size classes in the job generation process in Germany. It is based on a unique longitudinal data set covering all manufacturing establishments that existed in at least one year between 1978 and 1993 in the German federal state Lower Saxony. We find that gross job creation and destruction rates tend to decline with firm size, while net job creation rates and firm size are not systematically related when firms are classified according to their average number of employees in the base and end year. Small firms create (destroy) quite a large share of all new (lost) jobs.