Women and U.S. racial/ethnic minority students are underrepresented in engineering graduate education and engineering practice. Demographic homogeneity in engineering research teams can negatively affect individuals, innovation, and research outcomes. Thus, it is important to explore factors that influence student intentions to complete engineering degrees, particularly for groups historically underrepresented in engineering. Social Cognitive Career Theory guided the development of new items to evaluate self-efficacy, feeling welcome and included, relationship with principal investigator, and research group environment. Results with 295 engineering graduate students found that female sex, engineering self-efficacy, and feeling welcome and included were independently positively associated with commitment to complete an engineering degree. Feeling welcome and included operated 30% through self-efficacy and 70% directly. The effects of female sex were unmediated by self-efficacy. Results suggest that proximal and distal contextual factors may operate independently from self-efficacy to influence retention in graduate engineering programs.