This technical report presents the findings of Phase II of Immunisation of Older Adults in the Asia Pacific: Barriers, Facilitators and Strategies to Improve Access to Vaccines, a multi-country research study examining factors influencing vaccination uptake among older adults. Focusing on Hong Kong and Japan, the report explores shared challenges associated with rapidly ageing populations alongside high life expectancy. It identifies key barriers to immunisation, highlights best practices in vaccine delivery and stakeholder engagement, and proposes evidence-informed recommendations to strengthen vaccine confidence and improve uptake among older adults across the Asia Pacific region.