The purpose of this study was to examine the effect of a treatment package consisting of video and reflection, video feedback, and coaching on pre-service teachers' use of nonverbal immediacy behaviors as they delivered lessons to student avatars in mixed reality simulations. Pre-service teachers delivered lessons at three points of time over the course of a semester within a teacher preparation course. Following each simulation, participants received three components of a treatment package targeted at improving nonverbal immediacy behaviors of teachers. A mixed methods embedded research design provided for the collection of quantitative data, nonverbal immediacy scores, collected via the Nonverbal Immediacy Scale -- Observer Report. Qualitative data were collected via researcher observations of simulations and participant exit interviews. Statistical analysis resulted in a significant difference in pre-service teachers' nonverbal immediacy when Time 2 and Time 3 were compared. No additional significant differences resulted. An analysis of qualitative data resulted in two findings. Finding one was: Video and reflection, video feedback, and coaching fostered pre-service teachers' reflections on the simulated environment as they delivered lessons within the simulations. Finding two was: Video and reflection, video feedback and coaching within a mixed reality simulation environment improved pre-service teachers' use of nonverbal immediacy behaviors in student interactions. Connections to literature and implications are made. [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.]