It is presumed that when teachers engage in ongoing collaborative professional development, it will enhance their learning. It is then presumed these gains in teacher learning translate into improved student outcomes. Lesson study is one collaborative teacher professional development model that research has demonstrated can increase teacher and subsequent student learning. Yet, little is known about how the collaborative nature of lesson study supports teacher learning. Scholars believe it is the collaborative dialogue, supported by a facilitator, that teachers engage in that helps to promote teacher learning. For collaborative dialogue to be effective in promoting learning, it must be productive and include specific elements, supported by a facilitator. However, little is known as to how a facilitator supports productive talk and the specific strategies a facilitator employs to engage teachers in collaborative dialogue that then is presumed to result in teacher and subsequent student learning. Specifically, much less is known as to how a facilitator uses dialogic strategies to engage general and special educators in productive talk to support struggling readers across the multiple levels of tiered instruction. Thus, the purpose of this study was to examine a facilitator's use of dialogic strategies during lesson study sessions to learn which dialogic strategies promoted or hindered productive talk among general and special educators. To learn this, I examined the facilitation moves of one facilitator with one group of fourth-grade general and special education teachers from one school. I looked at lesson study sessions from the beginning, middle, and end of a year-long professional development on reading to identify specific dialogic strategies a facilitator used that promoted or hindered productive talk among general and special educators. I share my findings through vignettes and provide implications for future research and practice. [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.]