Substantial underreporting is typical in interviewing respondents on their drug use and other sensitive behaviors. This chapter reviews established strategies, self-administered questionnaires and indirect questioning techniques, for increasing the willingness of respondents to report stigmatizing behaviors. While these methods improve reporting, each has shortcomings and burdens which limit their effectiveness. A new computer-based self-interviewing approach which incorporates recorded audio playback of questions offers improved self-administered interviewing. The chapter discusses this technology, audio computer-assisted self-interviewing (audio-CASI), describing its features and positive results from the early research tests of the method.