Since 1991, State Impaired-Driving Assessments (IDAs) and Special Management Reviews (SMRs) have been conducted by the National Highway Traffic Safety Administration (NHTSA) to serve as a mechanism to assess the impaired-driving problem in the State, document the existing system, recommend improvements, and garner both political and public support to fund and implement improvements. Did these assessments and reviews serve the States as intended and provide a catalyst to reduce impaired driving? Almost half of the priority recommendations from IDAs in seven States and 60% of the priority recommendations in SMR States were implemented. Barriers to the implementation of some recommendations are discussed. IDAs and SMRs implemented at varying times were examined using logistic regression analyses of the Fatality Analysis Reporting System (FARS) for the years 1990 to 2008 to determine the effect they may have triggered on impaired driving rates in fatal crashes. States receiving IDAs and SMRs were compared to similar States not receiving them. Paired comparisons of similar States (e.g. IDA-State vs. non-IDA State) did not reveal any significant differences in impaired driving rates, but IDA and SMR States as a group showed significantly greater impaired driving declines in fatal crashes compared to non-IDA and non-SMR States as a group. IDAs and SMRs appear to provide a mechanism to examine the State’s impaired-driving program by an external team of experts and reveal areas where improvement is needed and confirm strategies that appear to be effective.