The use of open-ended questions in survey research has a very long history. In this paper, building on the work of Lazarsfeld and Schuman, we propose adapting open-ended questions to some functions in quantitative surveys for which they have not previously been used. We argue that adding such questions to computerized surveys, whether self- or interviewer-administered, is neither expensive nor time-consuming, and in our experience respondents are quite willing and able to answer such questions. This paper describes several uses of open-ended questions not yet fully exploited by others (e.g. Lazarsfeld 1944; Schuman 1966, 2008; Krysan 2002a, 2002b; Wenemark 2009). One is an exploratory function prior to the formulation of closed-ended questions. At this stage, it is important to include the entire range of possible responses—something that cannot easily be done with small locally invited samples. Once these have been determined and classified, it is possible to systematically query both respondents and nonrespondents in actual surveys. We have used this technique to ask for reasons for participating or not participating in specific surveys, to explore reasons for allowing or forbidding the use of paradata, and to investigate preferences for different formulations of informed consent statements. We have also put open-ended questions to two other uses. One is as a check on errors, the other is giving people a chance to explain their answers to a prior closed-ended question. The presentation will describe the results of these investigations and discuss methods for obtaining comprehensive, replicable, and reliably coded answers.