In many ways, higher educational systems in the United States are the most extraordinary in the world. Students come from all over to study in our institutes of higher learning. As our search for an explanation of how to facilitate student learning continues, the goal of this dissertation was to examine the heavily under-researched area of teacherstudent relationships as they relate to student understanding. Using the existing body of instructional communication research, the Student Understanding Model (SUM) is proposed and tested. Data collected from 302 undergraduate students was used to test the SUM. Results provide empirical support that relational messages account for approximately 26% of the variance in student understanding. Conclusions and implications from the current study were discussed.