This document summarizes a systematic review of theses from researchers in the Global OER Graduate Network (GO-GN). The GO-GN aims to raise the profile of open education research and support PhD students conducting research in this area. The review analyzed 50 theses from 14 countries across 10 categories related to open education, including project case studies, technical specifications, OER as a subject, policy, practitioners, developing nations, MOOCs, pedagogy, and open data/practice/access. The goal was to better understand the emerging field of open education research.