Continuous monitoring of breathing in infants is commonly performed using transthoracic impedance. This method employs skin surface electrodes measuring changes in electrical impedance and relates these changes to respiratory events. Typically, two electrodes on the infant's chest monitor both the ECG and breathing. We have attempted to identify separate electrode locations that give the best signal for breathing and ECG, and a single location that optimizes both of these signals. Thirty-seven infants were studied by placing 12 electrodes on the infant's chest and abdomen, and serially sampling pairwise combinations of electrodes. The optimal signal for breathing was obtained when electrodes spanned the diaphragm. Optimal ECG signal was seen with one electrode at the right mid-clavicle and one at the xyphoid. Clinicians should be aware of these locations in order to provide the best signal available.