Previous research extensively studied reasons for and ways to avoid low response rates, but it largely ignored the primary research issue of the degree to which response rates matter, which we address. Methodological survey research on response rates has been concerned with how to increase responsiveness and with the effects of response rates on variables' means and frequencies. More important to theory-oriented research, however, are effects of response rates on effect sizes (strength of relationships between variables). We examined recent survey research (446 correlations in 252 studies 2000-2020) on commonly studied variables in the example domain of organizational behavior, where surveys are especially common. We found a nonsignificant relationship (r = 0.01) between response rates and effect sizes. The relationship between sample sizes (the numerator in response rates) and effect sizes was weak but significant (r = 0.13, p = 0.01). Furthermore, there was no evidence for variability across studies and no curvilinear effects. Response rates on surveys have no noticeable effect on correlations nor therefore on theory development and testing.