The purpose of this study was to investigate the influence of private practitioner and educational advocate opinions on school-based administrators' decision-making thought processes when making a recommendation for special education eligibility. Special education eligibility is a school-based team decision that involves multiple stakeholders. Using Multiple Stakeholder Theory and Social Network Theory, supporting research shows that an individual may attempt to align with a stakeholder external to the decision-making group in an attempt to alter the power differential in an effort to sway the decision in his or her favor. School-based administrators are faced with this situation when parents employ private practitioners or educational advocates to add their "expert power" to the special education eligibility decision-making context. As instructional leaders for their schools, administrators must maintain political neutrality so students are not erroneously over- or underidentified as educationally disabled. Research has shown that leaders with greater efficacy beliefs are less influenced external agencies. School-based administrators (N = 56) with varying years of experience as special education administrators participated in this mixed methods study. Data were collected from a demographic survey, case vignettes, the School Administrators Efficacy Scale, and individual interviews. Private practitioner evaluations and educational advocate opinions had no significant influence on participating school-based administrators' recommendations for special education eligibility. When both are included among the data considered, a statistically significant relationship emerges but to a modest degree. Self-efficacy and years of experience as a special education administrator failed to be significant mediating variables in the relationship between the external factors (i.e. private practitioner evaluations and educational advocate opinions) and the school-based administrators' recommendations for special education eligibility. The majority of administrators reported that considering a combination of data, including school-based evaluations and teacher-provided classroom data, was most important information when considering a student's eligibility for special education services, and they cited other factors such as collegial support and relationships, team member communication, and their own focus on student advocacy to be the most influential factors on their decision-making processes. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]