Growing rates of nonresponse to telephone surveys can contribute to nonresponse error, and interviewers contribute differentially to nonresponse. Why do some telephone interviewers have better response rates than others? This study uncovered a critical behavior of successful telephone interviewers over the course of introductions: responsive feedback. Using detailed coding of telephone introductions, I explored interviewers' speech. Interviewers were most responsive to answerers in contacts that resulted in deferrals and least responsive in refusals. Practical applications for telephone interviewer training are discussed.