Abstract
Both actively and passively deflectable flexible ureteroscopes have a place in urologic practice. In general, we reserve the more expensive and more fragile actively deflectable instruments for those situations in which the passively deflectable instrument will probably fail, such as for examination of the entire intrarenal collecting system or the lateral or lower infundibula and for therapeutic procedures when the instrument cannot be directed to the area by passive deflection. Lesions within the ureter, the medial portion of the renal pelvis, and the upper infundibula usually can be reached easily with a passively deflectable instrument. I recommend having both types of instruments available.