Over the past 20 years, the way Mental Health research has been conducted in Europe has changed dramatically. To remain isolated is highly detrimental to the impact of the data collected and is making extremely difficult the dissemination of the results. The key word from the very beginning is collaboration: to facilitate it different European networks have been established.

A network should be considered as a flexible research structure in which the participants have common objectives, are using common tools and are looking for common outputs. To achieve this ambitious aim, instruments (both psychometric and neurobiological) have to be standardized and cross validated, methods for data acquisition have to be shared by all participants, a dedicated center for data management has to be chosen and, in case of specific procedures (neuro-imaging, genotyping etc...), the modalities for storage have to be defined in advance. Without these preliminary steps a network will function more as a patchwork of different centers than as a common repository of procedures, expertise and data. To tell it more directly the purpose of a network is not only to bring in more power by offering large recruitment possibilities, but is also to create an operational database with a true open access and to be the actual basis for a knowledge transfer benefiting to the scientific community. One of the main criticism which can be made to many of the European networks which have been established in the past is that they have functioned in a closed manner with no possibilities for external teams to have access not only to the data but as well to the procedures or to the tools used. The consequence has been the difficulty to replicate the results and the necessity...to recreate new networks, which is a waste of time and a waste of money! To avoid this kind of repetitive duplication of the same types of networks a better identification of existing networks is needed (how many European research networks on schizophrenia for example - a global map will be presented-), clear criteria have to be proposed for considering a network operational and a coordination with established joint programme initiatives has to be implemented.