Effective drug safety surveillance - pharmacovigilance - is dependent on the careful and dedicated actions of many different stakeholders, in particular the pharmaceutical industry, the regulatory authorities and the health care professionals. Also the patients play a key role. The gadolinium-NSF case provides a unique experience, which not only highlights the ideal function of the international pharmacovigilance system, but also points out the weaknesses of the system. In particular this article focuses on the crucial role of the health care professionals, who prescribe the medicinal products. Different from the regulatory authorities the health care professionals are in direct contact with the patients and are therefore able to observe the side effects of drugs, as these occur. It is important to realize, though, that the health care professionals do not have the overview concerning side effects occurring in relation to the use of medicinal products, neither for a particular drug nor in general. The overview of the safety profile of medicinal products can however be achieved by the regulatory authorities, provided that the first line observers report what they observe. It is also important to emphasize, that the health care professionals are not able to take legally based actions towards the marketing authorisation holders, and health care professionals are not able to request the implementation of risk minimizing measures aiming at improving the safety of their patients. Appropriate regulatory actions can be taken by the authorities, provided that there is sufficient evidence justifying the action in relation to a particular drug or class of drugs.