In an effort to bring together the broadest knowledge from a variety of usability testing study designs and methodologies, we analyzed studies using a narrative synthesis approach [13 ]. This approach is to not be confused with the narrative descriptions that accompany many reviews. Rather, a narrative synthesis is an attempt to systematize the process of analysis when a meta-analysis or a systematic review may not be appropriate because of the range of methodologies in the studies reviewed. Consistent with the narrative synthesis steps proposed by Popay [13 ], we conducted (1) a preliminary analysis of the included studies, (2) an exploration of relationships between included studies, and (3) an assessment of the robustness of the synthesis. Due to the exploratory nature of our review we omitted theory development from our synthesis process [13 ]. Preliminary synthesis consisted of extracting the descriptive characteristics of the studies in a table and producing a textual summary of the studies employing a specific usability testing design/methodology. When appropriate, a thematic analysis was used to extract themes from the cluster of studies within a given methodological domain. The subsequent narrative results represent the main areas of knowledge available about the types of usability testing methods employed with technology-based diabetes education and behavioral interventions from 2009–2013. We conclude with a reflection on our synthesis process and implications for technology-based intervention research in diabetes.