We welcome this opportunity to respond to previously published commentaries by Drs Haggerty, Starfield, and Dutton on our discussions of how cost sharing affects the use of medical services and health status.1,2 Our purpose in responding is threefold: to reiterate succinctly the major conclusions of the Rand Health Insurance Experiment, to respond to issues raised by the commentators, and to emphasize certain points of agreement with them. Our goal is to promote a better understanding of the experiment and spur further discussion about the structure of health insurance for children. WHAT DID WE SHOW? In the Rand Health Insurance Experiment, a total of 1,844 children from six areas participated in a randomized experiment on the effects of cost sharing in health insurance policies.