A national telephone survey was conducted to examine potential differences between National Association of School Psychologists (NASP) members and non-NASP member school psychologists. Identified schools were contacted by telephone and the researchers asked to speak with the school psychologist. A sample of 124 practicing school psychologists was obtained. Overall, 57.3% (n = 71) of respondents were NASP members, and 42.7% (n = 53) were not. In most respects, current results were similar to NASP-member-only surveys. Current results suggest that previous studies overestimated the proportion of NASP members among school psychologists and may have underestimated the total number of school-based practitioners. Significant differences between NASP members and nonmembers were found in ethnicity, national certification, professional organization membership, and use of Curriculum Based Measurement. Results are discussed in the context of previous national surveys. (Contains 3 tables.)