A new Doppler probe inside a needle was evaluated in a group of infants and children to assess its suitability for subclavian venous access. While the efficient use of this device required learning a new technique, we found the device useful to accurately locate the subclavian vein and differentiate it from the artery in all patients weighing more than 3 kg. This device will be most helpful in cases of difficult access, eg, scar from previous access, obesity, or edema. © 1993 W.B. Saunders Company. All rights reserved.