Urinary tract catheters are hollow andflexible tubes used to facilitate urine output or to achieveurine transit through them. We can find different typesof catheters depending on the purpose they have beendesigned for: urethral, cystostomy and ureteral cathetersamong others. We review the indications for insertionof these catheters, their designs, composition, coveringmaterials, insertion techniques and associated complications.Pediatric catheters are behind what is producedfor adults, so we perform a bibliographic review abouturinary catheters in general with emphasis on the pediatricpatient.