To what extent does perceived safety and security influence the amount and pattern of use on public transportation systems? While it is assumed to be a major factor in modal choice, there is little empirical research to show that it is. The major relevant studies are briefly reviewed. Then the results of recent surveys of both users and non-users of public transportation are presented. Perceived safety is discussed in relation to frequency of system use, sex, age, and sources of information about transit crime. The influence of other factors on mode choice are also reported.