Computer assisted telephone interviewing, and to a lesser degree, computer assisted face-to-face interviewing, are by now widely used in survey research. Recently, self-administered forms of computer-assisted data collection, such as web surveys, have become extremely popular. Advocates of computer assisted interviewing (CAI) claim that its main advantages are improved data quality and lower costs. This paper summarizes what is currently known about computer assisted data collection methods. The emphasis is on data quality and the influence of technology on the respondent.