&NA;The microscopic evaluation of urinary sediment dates back to the 19th century, when abnormal cellular findings were discovered in the urinary sediment of men subsequently found to have bladder cancer. In the mid‐20th century modern urine cytology was introduced and applied in the clinical detection of bladder cancer. Over the past 20 years, urine cytology has commonly been used in the diagnosis and management of urothelial carcinomas. This article reviews the uses of urinary cytology in clinical urologic practice, describing its application and value in the diagnosis and management of urinary tract malignancies.