Global access to practitioner training in the clinical engagement of fathers in family-based interventions is limited. The current study evaluated the feasibility of training practitioners in Canada and UK using online training developed in Australia by examining improvements in practitioner confidence and competence in father engagement, training satisfaction, qualitative feedback, and benchmarking results to those from an Australian sample. Practitioners were recruited to participate in a 2-h online training program through health services and charity organisations. The online program required practitioners to watch a video and complete self-reflection exercises in a digital workbook. Pre- and post-training measures were collected immediately before and after the online training program. The results indicated significantly large improvements in self-reported confidence and competence in engaging fathers following training, with levels of improvement similar to those found in Australia. Training satisfaction was high and qualitative feedback suggested providing local resources and increasing representation of social diversity could improve training relevance in local contexts. The findings suggest online training in father engagement can contribute to global workforce development in improving practitioners’ skills in engaging fathers in family-based interventions.