In the spring of 1993 a meeting of the European Charcot Foundation was held in Bari as it was quite clear that there was a renaissance of Italian interest in cerebro spinal fluid. Two of the influential figures with a long-standing commitment to this field were Professor Paolo Livrea and Dr. Maria Trojano. At this meeting we con sidered the possibility of collecting together the various papers which had been presented, however the idea evolved further to the present volume, which incor porates a broader view. This starts with the anatomical approach, including neuro pathology, CSF cells and MRI correlations. It also includes virology, physiology of the blood-CSF barrier and the immunology of intrathecal responses. It further con siders the relevance of the CSF parameters to therapy. Finally, the importance of quality assurance and handling of the precious fluid is discussed. The original plan was to have the book published in Italian, but we are grateful to the publishers for allowing English text, in order to have a wider, international audience. As is fate of any book, interest in this area has been accelerated considerably; nevertheless we hope this provides a summary from a multi-disciplinary point of view. From a pu rely personal point of view, it certainly reflects the warmth of feeling which was evident at the meeting, and which led to the toast "Arrivederci, Bari." E. J."