Group A rotaviruses are the most common cause of severe gastroenteritis worldwide. The incidence and distribution of group A rotavirus sero/genotypes varies between geographical areas during a rotavirus season, and from one season to the next. In addition, cocirculation of genetically diverse multitypic rotaviruses and of intratypic variants in any one place and time is common. Assuming widespread use of rotavirus vaccine in the near future, comprehensive surveillance of natural rotavirus infections is vital. EuroRotaNet has been established in order to gather comprehensive information on the rotavirus types co-circulating throughout Europe. The main objectives of the network are to (i) develop methods and algorithms for effective rotavirus strain typing and characterisation, (ii) describe in detail the molecular epidemiology of rotavirus infections in Europe, (iii) monitor the effectiveness of current genotyping methods and respond to changes associated with genetic drift and shift, and (iv) monitor the emergence and spread of novel rotavirus strains within Europe. This infrastructure may serve as a platform for future surveillance activities and nested studies for evaluating the effectiveness of a rotavirus vaccine in the general population. Studies to monitor the reduction in disease associated with common rotavirus types, the possible vaccine-induced emergence of antibody escape mutants of genotypes other than those included in the vaccine and of reassortment between vaccine and naturally circulating wildtype strains are required.