Since 1997, avian influenza A(H5) viruses have threatened human health, prompting CDC to develop response tools to detect, treat, and prevent infections. Beginning in 2006, CDC and partners created multidisciplinary training programs to strengthen preparedness, covering clinical management, epidemiology and response, laboratory, and veterinary response. First delivered in Bangkok in 2006, these trainings expanded globally through cascaded workshops and were adapted for US domestic preparedness. Trainings were updated to address the threat of A(H7N9) viruses in 2017, and more recently to address changes in circulating influenza viruses. Sustained readiness through continued harmonized training remains critical for early response and global health security.