In spring 2004 an accumulation of cases of invasive meningococcal disease was observed in the Allgaeu/Bavaria. Investigations of the isolates showed, that four cases in neighbouring municipalities of the district Oberallgaeu were caused by an identical strain of serogroup C. The particular strain was a rare variant of the so called ET-15 clone, which had caused several outbreaks of severe meningococcal disease among young people in the past, for example in Rottal/Inn (1998), Karlsruhe (1999 - 2000) and Schwerte (2003). The involved health authorities had to decide, which intervention strategies were reasonable and appropriate to the given situation. An epidemiological assessment of the situation was made by the Bavarian Health and Food Safety Authority (LGL) using the recommendations of the permanent immunization committee at the Robert Koch-Institute and of the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention (CDC) . The LGL together with the Robert Koch-Institute and the national meningococcal reference centre concluded that the situation fulfilled the criteria for a vaccination indication in accordance with section sign 20 Abs. 5 of the infectious disease control act (Infektionsschutzgesetz, IfSG). On the basis of this assessment the responsible regional health authority issued a public recommendation for vaccination and the district health authority of the Oberallgaeu was assigned to implement a vaccination campaign. The Oberallgaeu health authority offered vaccination sessions to the public in the concerned communities. The target group comprised babies, children, young people and adults up to twenty years, who lived in the concerned communities in the northern part of Oberallgaeu, as well as close contacts of cases and members of the above age group, who had visited communal facilities in the communities concerned. Our report describes the implementation of the vaccination campaign.