Men with pain or a burning sensation on urination should be evaluated with a thorough history, a focused physical examination and urinalysis (both urine dipstick and microscopic examination of the urine specimen). Although dysuria may be caused by anything that leads to inflammation of the urethal mucosa, it is most often the result of urinary tract infection. In younger patients, the infectious agent is usually a sexually transmitted organism such as Chlamydia trachomatis. In patients over 35 years of age, coliform bacteria predominate. Infection in older men most often occurs as a result of urinary stasis secondary to benign prostatic hyperplasia. Other conditions that may cause dysuria include renal calculus, genitourinary malignancy, spondyloarthropathy and medications. Successful treatment of dysuria depends on correct identification of its cause.