A presumed rise in the prevalence of atopic diseases in industrialized countries is currently subject to extensive discussion. Due to a lack of epidemiological longitudinal studies, the controversy among the experts was based mainly on speculation. Only recently have data from various European countries confirmed an increase in atopic diseases. Studies from Sweden, Switzerland and Denmark showed a definite increase in atopic diseases. Studies from Sweden, Switzerland and Denmark showed a definite increase in the prevalence of hay fever, bronchial asthma and atopic eczema, respectively. Japanese investigators have concerned themselves with the putative role of air pollutants in this development. They were able to show a relationship between exposure to particulate air pollutants (diesel exhaust) and the prevalence of mountain cedar pollinosis. To date a lack of baseline data has hampered the evaluation of epidemiologic trends in Germany. We performed a pilot survey study involving more than 1000 pre-school children that yielded initial evidence of an unexpectedly high prevalence of allergic conditions in Bavaria. A comparison with current epidemiologic data from other European countries suggests an increase in allergies in Germany similar to that observed elsewhere.