In this randomized multiple baseline across participants single-case design study, pre-service special education teachers received a modified Talk Aloud Problem Solving (TAPS) intervention to improve their use of problem-solving verbal behavior and reasoning skills when making instructional decisions. Special education teacher candidates may have limited opportunities for meaningful practice with the problem-solving required to synthesize various information about student strengths, needs, and current performance into high-quality instructional decisions. This is evidenced in the field by IEP analyses that consistently demonstrate poor quality documents that lack evidence of strong instructional decisions. In this study, instructional decisions include a goal, an evidence-based instructional practice that will be used to reach that goal, and modifications or accommodations based on the student's needs that ensure access to the general curriculum. Dyads were trained using the TAPS curriculum to use effective problem solving and active listening language when presented with a student vignette. Visual analysis, Tau-U overlap analysis, and a between-case standardized mean difference effect size were calculated. Overall, the TAPS intervention improved the use of problem-solving language but an effect on decision-making quality could not be established. Implications and future research are discussed. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]