The purpose of this research was to develop and validate a set of core competencies of effective school-based consultants for preservice school psychology consultation training. With recent changes in service delivery models, psychologists are challenged to engage in more indirect, preventative practices (Reschly, 2008). Consultation emerges as one such recommended practice for school psychologists (Ysseldyke et al., 2006). However, despite recommendations and mandates from accrediting bodies, there is a lack of consensus to guide training in school consultation. This research involved a systematic literature review and Delphi study to determine core competencies for contemporary school consultants, specifically for school psychologists. An expert panel for the Delphi portion of the research was drawn from a consultation training interest group, a consultation research group, and editors of a consultation training journal in order to sample the leaders in the field of consultation research and training. Multiple iterations of the Delphi study, as recommended in the literature, were conducted to obtain consensus on the fundamental skills and knowledge. Four multicultural consultation competencies from previous research (Rogers & Lopez, 2002) were included to obtain current ratings, and personal characteristics from the literature were rated in terms of essentialness and "trainability." Results from two iterations of survey material indicated a list of 35 core competencies to guide training which received Essential ratings by 75% or more of participants. The four multicultural competencies were rated more highly by the current participants than by Rogers and Lopez's participants 10 years ago. In addition, several personal characteristics were identified as essential to school-based consultants; however, some of the highest rated characteristics were considered least "trainable" by the participants. Finally, implications for consultation training, limitations, and future directions were explored. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]