Researchers are often skeptical of sexual behavior surveys: Respondents may lie or forget details of their intimate lives, and interviewers may exercise authority in how they capture responses. We use data from a 2010-2011 cross-sectional sexual behavior survey in rural South Africa to explore who says what to whom about their sexual lives. Results show an effect of fieldworker age across outcomes: Respondents report "safer," more "responsible" sexual behavior to older fieldworkers, and an effect of fieldworker sex; men report more sexual partners to female fieldworkers. Understanding fieldworker effects on the production of sexual behavior survey data serves methodological and analytical goals.