This safety report represents the culmination of a year-long National Transportation Safety Board (NTSB) effort focused on the problem of substance-impaired driving. The report addresses the necessity of providing all the following elements to achieve meaningful reductions in alcohol-impaired driving crashes: stronger laws, improved enforcement strategies, innovative adjudication programs, and accelerated development of new in-vehicle alcohol detection technologies. Moreover, the report recognizes the need for states to identify specific and measurable goals for reducing impaired driving fatalities and injuries, and to evaluate the effectiveness of implemented countermeasures on an ongoing basis.