Employers do not seem to implement testing programs because of perceived problems of drug abuse in their workplaces. Instead, they may assume that some employees use drugs or be reluctant to be the only company without a testing program. Thus, the existence of drug testing acts as a stimulus to further drug testing. However, these programs may push chronic drug users from the ranks of the self-supporting to the ranks of the dependent poor. Testing for marijuana presents special issues because of the longer period it is detectable in urine and because of its use by people in all socioeconomic classes. At some point society will either need to condone marijuana use or condemn it more strongly to deter its use. The confidentiality surrounding drug testing raises issues of social control, social fragmentation, and testing's disciplinary power, particularly with respect to employees who test negative. Figure and 46 footnotes.