Despite persistent effort at the local, state, and federal levels, alcohol-related crashes still account for 39% of traffic fatalities. Vehicle-based countermeasures have the potential to address this problem and save thousands of lives each year. Driving simulators provide an ideal platform to safely develop countermeasures and assess their potential. Vehicle-based countermeasures depend on developing an algorithm that uses driver performance to assess impairment. The National Advanced Driving Simulator (NADS) at the University of Iowa is conducting a project for the National Highway Traffic Safety Administration to collect the data needed to develop an algorithm sensitive to alcohol impairment. This experimental plan for data collection will support the development of algorithms to estimate alcohol impairment in real time. Data collection will involve multiples of 54 drivers from three age groups (21-34, 38-51, and 55-68 years of age) driving on three types of roadways (urban, freeway, and rural) at three levels of alcohol concentration (0.00%, 0.05%, and 0.10% BAC). The scenarios used for this data collection were selected so that they were both representative of alcohol-impaired driving and sensitive to alcohol impairment. Through this project, NADS will develop a research plan document containing three sections: 1) considerations and requirements for selecting scenarios that are both representative of alcohol impaired driving situations and sensitive to the effects of alcohol impairment; 2) the experimental plan that describes the methods used to collect data for algorithm development; 3) the evaluation of this experimental design with a plan for the pilot testing. For this project, WTI will conduct specific subtasks for the University of Iowa related to review and evaluation of the scenarios and experimental plan.