Results of driving performance evaluations on a vehicle simulator indicated that there was a higher degree of inattention and a greater potential safety hazard associated with manual dialing on HHMTE than with memory- and voice-activated dialing of HFMTE. No differences were found in answering. A crash-worthiness investigation showed that risks of injury from phones striking passengers was relatively insignificant. Current designs were deemed acceptable, although certain features reduced the likelihood of injury. An analysis of '911' calls showed that MTE provides a primary safety benefit in emergency situations. A no-charge policy for '911' calls resulted in a 75-percent increase in such calls, primarily to report accidents, traffic hazards, and fires. To further assess the impact of these systems on traffic safety, two possible studies are proposed: a comparison of MTE user accident records before and after acquiring the MTE with those of a control group, and a study of MTE presence and use as related to traffic accidents. In addition, a plan for promoting public awareness of MTE safety issues was developed. Supplemental research information, figures, tables, illustrations, and 47-item bibliography.