Exploring sustainable primary care responses to intimate partner violence in New Zealand: Qualitative use of complexity theory GearC Koziol-MclainJ EppelElizabeth 2020 © © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. Objective To explore what affects sustainable responses to intimate partner violence within New Zealand primary care settings using complexity theory. Design Primary care professional interviews on intimate partner violence as a health issue are analysed using a complexity theory-led qualitative research methodology grounded in poststructuralism. Setting Four general practices in one region of the North Island of New Zealand, two serving a general patient population and two adopting an indigenous approach. Participants Seventeen primary care professionals and management from the four recruited general practices. Results The complex adaptive system approach the ' Triple R Pathway', calls attention to system interactions influencing intimate partner violence responsiveness across health system levels. Four exemplars demonstrate the use of the Triple R Pathway. Two key system areas challenge the emergence of primary care responsiveness: (1) Non-recognition of intimate partner violence as a key determinant of ill-health. (2) Uncertainty and doubt. Conclusions The relationship between intimate partner violence and ill-health is not well recognised, or understood in New Zealand, at both policy and practice levels. Inadequate recognition of socioecological determinants of intimate partner violence leads to a simple health system response which constrains primary care professional responsiveness. Constant intervention in system interactions is needed to promote the emergence of sustainable responses to intimate partner violence.