Working conditions in the science system have long been complained about as insecure and lacking in perspective. It is an open question who could benefit from more secure employment. While a widespread rhetoric in political debates and some economic approaches suspect that greater job security undermines scientist’s motivation, efforts and performance, psychological approaches on work and motivation see increasing satisfaction on the part of scientists as a driver for the development of higher performance potential. We are investigating the relationship between contract situation, satisfaction and performance in science on the basis of a representative sample of 4,134 postdocs from all universities in Germany. The results show positive effects of secure employment on both satisfaction and output. However, the output effect is only partly mediated by satisfaction. In contrast to earlier studies, relevant contextual characteristics of the work situation are controlled for, so that the effect of the secure employment is more clearly carved out. The study refutes negative attributions of permanent positions on work results and thus the hammock argument. Thus, all parties may benefit from stable jobs for researchers.