A comparison of the Q3 and Hybrid III 3-year-old crash test dummies is presented in this paper. The performance of the dummies were compared in sixty biofidelity tests, seventy-seven static out-of-position airbag tests and sixty- three calibration tests. Various time histories and other data pertaining to accelerations, deflections, forces and moments are compared. In addition, the ease of positioning, handling, and the durability of the dummies in various out- of-position test configurations was assessed.Both the Q3 and Hybrid III 3-year-old dummies were calibrated to their respective specifications. The Hybrid III 3-year-old met its calibration requirements, while the Q3 did not always meet its own calibration requirements. The calibration specifications of the Q3 dummy need to be re-examined and possibly refined.The biofidelity of the Q3 and Hybrid III 3-year-old dummies were evaluated in both frontal and lateral test modes. Each dummy was evaluated against its own and the other''s specified requirements, when possible. In the frontal test mode, the Hybrid III 3-year-old acceptably met all of its requirements. The Q3 dummy did not meet all of its own frontal biofidelity requirements. Based on these results, the Hybrid III 3-year-old is more biofidelic for primarily frontal loading conditions.With respect to the lateral biofidelity specifications, neither the Hybrid III 3-year-old nor the Q3 dummy met the requirements for the thorax and pelvis tests performed. Both dummies met the head drop requirements. Neither dummy is recommended for lateral loading conditions. For lateral testing where only the head is impacted, the Hybrid III 3-year-old could be used.In general, the responses of both dummies were repeatable in both the frontal and lateral biofidelity tests performed.The Hybrid III 3-year-old and the Q3 dummies were evaluated in static out- of-position airbag tests with three different side airbag systems (two seat- mounted and one door-mounted system), and one frontal passenger airbag system. Throughout this testing, the Q3 resultant head accelerations exhibited an excessive amount of high-frequency noise causing this dummy to be unacceptable for static out-of-position airbag testing. No significant issues were found with the Hybrid III 3-year-old.It was also determined that the Q3 dummy was more difficult to position repeatedly than the Hybrid III 3-year-old. This was due to the dummy''s construction and its lack of rigid landmarks.