Chemical immobilization often is the most effective method for capturing white-tailed deer (Odocoileus virginianus). Numerous chemical immobilization agents are available. We compared the efficacy and physiological effects of 2 white-tailed deer immobilizing agents: medetomidine-ketamine (M-K) antagonized with atipamezole, and xylazine-Telazol (X-T) antagonized with tolazoline. Mean induction time was longer and more variable for M-K. Mean reversal time and total down time was longer and more variable for X-T. Mean blood oxygen saturation (SpO2) in subjects treated with M-K was lower immediately following induction. We detected no differences in mean SpO2 at >5 minutes post induction or for mean rectal temperature or pulse rate at any time during the monitoring period between the 2 groups. Each agent appeared to offer advantages and disadvantages, depending on the specific circumstances of the capture event.