I investigated the presence, utility, and emergence of tacit knowledge in 9 study participants who used assistive-augmentative technology. I conducted phenomenologic interviews, audio-taping, and transcribed the interview with the written consent of the participants. Sixteen highly trained experts critiqued the final product of the interviews and answered a 25-question survey instrument. Non-parametric statistical processes were chosen to conduct inferential hypotheses testing. Wilcoxon-Mann Whitney U tests and Kruskal-Wallis One-Way ANOVA (alpha level of 0.05) were used for questions 1-10, and a 2 x R (R = 3 or 4) contingency table and Fisher's Exact Chi-Square were used for questions 11-25. The responses to survey questions showed no statistically significant differences or interaction for the variables gender, expertise, and service (p < 0.0017). Qualitative analysis found discernable heuristics and ideation that was indicative of the presence of implicitly learned tacit knowledge in study participants; the utility of tacit knowledge emerged during direct observation or when participant's engaged in analogy, storytelling, and metaphor. The participants in this study used introspeculation, a learning style framed by reflection and introspection on the validity of one's own knowledge and the value of what is learned from life experience and in the classroom. The introspeculative examined the presence and utility of tacit knowledge in decision-making, and questioned the veracity of sources and resources that guide them on the path of life. The study suggested that tacit knowledge not only informs the practice of therapists and technology users but may assist classroom teachers facing student involvement in individual education plans (IEPs), Individuals with Disabilities Education Act (IDEA), or section 504 of the Americans with Disabilities Act (ADA). [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.]