Abstract Purpose The most complex injuries are usually least often encountered by trauma team members, limiting learning opportunities at work. Identifying teaching formats that enhance trauma skills can guide future curricula. This study evaluates self-assessed technical and nontechnical trauma skills and their integration into novel work situations for multidisciplinary trauma masterclass participants. Methods This mixed methods study included participants of a multidisciplinary 3-day trauma masterclass. Ratings of trauma skills were collected through pre- and postcourse questionnaires with 1-year follow-up. Qualitative semi-structured interviews 9 months postcourse focused on the course format and self-perceived association with technical and nontechnical skills applied at work. Results Response rates of pre- and postcourse questionnaires after 1 day, 3 months, and 1 year were respectively 72% (51/71), 85% (60/71), 34% (24/71), and 14% (10/71). Respondents were surgeons (58%), anesthesiologists (31%), and scrub nurses (11%). Self-efficacy in nontechnical (mean 3.4, SD 0.6 vs. mean 3.8, SD 0.5) and technical (mean 2.9, SD 0.6 vs. mean 3.6, SD 0.6) skills significantly increased postcourse (n = 40, p < 0.001). Qualitative interviews (n = 11) demonstrated that increased self-efficacy in trauma skills was the greatest benefit experienced at work. Innovative application of skills and enhanced reflection demonstrate adaptive expertise. Small-group case discussions and the operative porcine laboratory were considered the most educational working formats. The experienced faculty and unique focus on multidisciplinary teamwork were highly valued. Conclusion Course participants’ self-assessed work performance mostly benefited from greater self-efficacy and nontechnical skills. Future trauma curricula should consider aligning the teaching strategies accordingly.