The authors expand on research evaluating public school response to school choice policies by considering the particular influence of voucher programs for disabled students--a growing type of choice program that may have different implications for public school systems from those of more conventional choice programs. The authors provide a theoretical framework to show that special education vouchers could influence both school quality and the likelihood that a school will choose to identify the marginal child as disabled. Using a rich panel data set from Florida, the authors find some evidence that competition from a voucher program for disabled students decreased the likelihood that a student was diagnosed as having a mild disability and was positively related to academic achievement in the public schools. (Contains 11 tables and 14 notes.)