Two studies examined the change in self-efficacy of practitioners after attending Triple P training and the moderators that affect training outcomes. Study 1 used a large multidisciplinary sample of health, education, and welfare practitioners ( N = 37,235) came from 30 countries around the world, which all participate in a Triple P professional training course during 2012-2019. This study assessed practitioners' overall self-efficacy and their consultation skills efficacy prior to training, immediately following training, and at six- to eight-weeks follow-up. Participants reported significant improvements of their overall self-efficacy and their consultation skills self-efficacy. There were significantly small differences based on practitioners' gender, disciplines, education levels, and country location. Study 2 examined the training outcomes of videoconference-based training (following the COVID-19 pandemic) compared to in-person training ( N = 6867). No significant differences were found between videoconference and in-person training on any outcome measure. Implications for the global dissemination of evidence-based parenting programs as part of a comprehensive public health response to COVID-19 was discussed.