In 2005, five individuals of Diabrotica virgifera virgifera were captured on traps at four locations in the Netherlands. These locations were: Moorveld (near Maastricht airport), Badhoevedorp (near Schiphol airport), Woerden en Ter Aar. At each location a focus zone of 1 km radius around the field, where the insect was captured, was demarcated and control measures were imposed. The control measures consisted of insecticide applications, crop rotation (1 : 3), hygienic measures for machinery and a prohibition on the movement of soil and fresh maize. Moreover, a safety zone of 5 km radius around the field of capture was demarcated. In this zone also a crop rotation was imposed (1 : 2). In both zones the monitoring with traps was intensified. In addition a buffer zone of 50 km radius around the field of capture was demarcated. In this zone monitoring was also intensified. Monitoring traps were replaced every 4 weeks and checked every 2 weeks. Following intensive monitoring no more beetles were captured at three locations (Moorveld, Badhoevedorp and Woerden) and one additional beetle was caught in the monitoring traps located around Ter Aar. This indicates that no populations were established at the four sites. The capture of five individuals is probably due to insects that were introduced by air and/or road traffic. The monitoring will be continued in these demarcated areas in 2006 and 2007.