To survey the frequency of Lyme borreliosis (LB) and to evaluate its clinical presentation in Europe, we performed a questionnaire interview of a sample of physicians involved in the care of patients with LB. Reference laboratories in 15 European countries agreed to participate by distributing questionnaires to those clinicians who most frequently requested LB serology for their patients. The mean number of cases of LB per physician per country showed a longitudinal geographical gradient, with a higher number of patients seen in Eastern and Central Europe than in Western Europe. Skin involvement was seen in 58.9% of the patients, neurological involvement in 34.3%, joint involvement in 15.4% and cardiac involvement in 2%. About 30% of the patients had multisystem involvement. The frequency of the different manifestations varied greatly between countries. The frequency of diagnosis of LB and the number of serological tests requested were inversely correlated.