In summer of 2005 levels of ground-level ozone were high in southern Europe with widespread exceedances of the information threshold value (180 micro g/m3) laid down in the ozone directive (2002/3/EC). The frequency of exceedances of the information threshold was similar to earlier years, except for the summer 2003, which had a record number of exceedances. The highest one-hour ozone concentration in summer 2005 (361 micro g/m3) was observed in Portugal. Other high hourly ozone concentrations between 360 and 300 micro g/m3 were reported from Greece, Italy, France, Romania and Spain. The directive's long-term objective to protect human health, an ozone concentration of 120 micro g/m3 over 8 hours, was extensively exceeded in the EU and other European countries. In large parts of Europe the target value to protect human health was also exceeded.