Summary. Recommendations for antimicrobial treatment and prophylaxis of urinary tract infections (UTI) have been made according to the results of investigation of resistance of the most frequent causative agents of UTI to antimicrobial drugs. This investigation has been conducted for the past seven years by the Committee for monitoring bacterial resistance to antibiotics in the Republic of Croatia, with consensus of eight professional societies of the Croatian Medical Association. Uncomplicated cystitis is treated 1, 3, or 7 days, complicated 7 days, pyelonephritis 10–14 days, and complicated UTI 7 to 14 days, rarely longer. For the treatment of cystitis fluorokinolons, nitrofurantoin, betalactam antibiotics, and in the fields of lower resistance trimethoprim/sulfamethoxazol are being used. Single treatment with fluorokinolons is administered to otherwise healthy young women with normal urinary tract in whom cystitis symptoms have been present for less than 7 days. Empiric antimicrobial treatment of pyelonephritis, recurrent and all complicated UTI must be reviewed after urine culture finding is obtained. In the treatment of bacterial prostatitis and febrile UTI in males, the drug of first choice is ciprofloxacin. Asymptomatic bacteriuria (AB) is treated in pregnant women, newborns, preschool children with urinary tract abnormalities, before invasive urologic and gynecologic procedures, in kidney transplant recipients, and in the first days of short term urinary bladder catheterization. Recommendations for the treatment of AB in patients with diabetes mellitus have been controversial in the past two years. Antimicrobial prophylaxis is administered mostly one hour prior to the diagnostic or therapeutic invasive urological procedure, using selected antimicrobial agents.