This text consists of the proceedings of the FEMS Symposium on Genes and Proteins Underlying Microbial Urinary Tract Virulence: Basic Aspects and Applications, held September 16-19, 1999, in Pecs, Hungary. Urinary tract infections are among the most frequent diseases caused by microbial pathogens. In this volume, researchers, clinical microbiologists and clinicians exchange ideas covering four major aspects of this important topic: genetic information, synthesis and assembly of virulence factors in urinary pathogens; regulation of genes involved in the phenotypic appearance of virulence; host-parasite interactions determining the process and outcome of the infection; and possible applications of the above aspects in diagnosis, therapy and prevention.