A study examined the effectiveness of a new computer-based multiphasic approach to identifying "at-risk" older drivers and remediating deficits in their driving and traffic safety attitudes, knowledge, and skills. Data collected from 250 older drivers in 3 states were used to develop specifications for computer-based driver improvement modules. The effectiveness of the new program, which links the Older Driver Self-Assessment Inventory (ODSAI), Older Driver Improvement Program (ODIP) and Older Driver Simulation Program (ODSP), was assessed in a study involving control groups and pretests/posttests. The study established that, although exposure to the ODSAI resulted in improved attitudes regarding driving and traffic safety and exposure to the ODIP resulted in increased knowledge of driving and traffic safety, exposure to the ODSP alone resulted in little change in driving and traffic safety skills. The multiphasic approach incorporating all three components resulted in improvements in drivers' skills as well as in their attitudes and knowledge. (An 81-item bibliography and 27 figures/tables are included. Appendixes include copies of all assessment instruments used, the simulation protocol, abstracts/summaries of the study presented at four conferences, and a supporting statistical analysis.) (MN)