This experiment investigated the effects of survey administration mode (Web vs. paper and pencil) and survey length (short or long) on the responses of a large sample of primary and secondary school professionals in the U.S. The 812 participants in this study were part of an initial random sample of 1,000 individuals representing 5.81% of the membership of a national professional organization. The participants were randomly assigned to each of the four treatment conditions. Results indicated (1) substantially lower response rates for Web surveys than for same-length paper surveys; (2) a higher response rate for short surveys than for long surveys with paper, but not Web, questionnaires; and (3) a younger age for Web respondents, as compared with their paper counterparts. In light of prior research, we suggest that paper-and-pencil methods be used for surveying professionals in primary and secondary school settings.