Dennis has supported university writers since 1993 when he began tutoring at the Washington State University (WSU) Writing Center. While at WSU, Dennis also taught first-year writing and programmed his first Online Writing Lab. Since coming to Oregon State University in 2004, he has worked as the OSU Writing Center Assistant Coordinator, Coordinator, and Director. He works extensively with writing technologies and was a lead programmer for the Write 365 project, which is a component of the Writing 121 curriculum.

In addition to teaching writing for the School of Writing, Literature, and Film, Dennis is the Director of the Graduate Writing Center.