We will initiate a New Zealand arm of the ITC project - a leading international tobacco control collaboration. The aim is to support the achievement of New Zealand's Smokefree2025 goal and promote equal enjoyment of the health, social and economic benefits that follow among Maori, Pacific peoples, and lower SES groups. We will establish a cohort of smokers and recent quitters who will be followed up over time to explore patterns of behaviours (e.g. quitting, relapse, use of e-cigarettes) and identify their determinants and outcomes. We will evaluate the impact of interventions within the cohort and through cross-country comparisons with other ITC countries, including an indigenous cohort in Australia. We will include adjunct studies to investigate emerging issues in more depth, focusing on Maori and Pacific smokers. Understanding smokers’ varied and emerging behaviours and evaluating interventions will help monitor of progress towards, and the develop strategies to achieve, the Smokefree 2025 goal.