Pacific peoples in New Zealand are a youthful population with over one-half (57%) aged under 25 years. In general, Pacific peoples report high levels of life satisfaction, family wellbeing, and strong social connections and support from family and friends. However, a disparity in mental health outcomes exists between Pacific peoples and other New Zealanders. The Pacific Islands Families: Thriving Pacific Young Adults (PIF: TPYA) study seeks to explore how cultural identity, family functioning, and employment impact the mental wellbeing of a cohort of 850 Pacific young adults (aged 22 years). Based primarily in South Auckland, New Zealand, the study will collect evidence which will be directly used by key stakeholders and agencies to design policies and implement strategies to ensure our growing numbers of vibrant and gifted Pacific young adults can thrive and contribute to a prosperous future for their families and the wider New Zealand society.