This paper examines data on the question of possible differences between benzodiazepines in abuse liability and potential for causing physical dependence. The data on potential for causing physical dependence indicates that all benzodiazepines cause physical dependence and there is little evidence for substantial differences between them in this respect. The evidence for substantive differences between benzodiazepines with respect to abuse liability is reviewed: problems with methodology and with definitions make problematic the assertion of some authors that there are clinically meaningful differences in abuse liability. There is general agreement that all benzodiazepines have at least some abuse liability.