Public Mental Health as a Complex System: From Individual Behaviour Change to Collective Capability and Community Infrastructure

TY - JOUR

T1 - Public Mental Health as a Complex System

T2 - From Individual Behaviour Change to Collective Capability and Community Infrastructure

AU - Hill, Taylor G.

N1 - Copyright: © 2026 The Author(s). Mental Health Science published by Wiley Periodicals LLC.

PY - 2026/9

Y1 - 2026/9

N2 - Public mental health agendas increasingly recognise that mental health outcomes are shaped by social, economic, and environmental conditions, yet much population-level activity continues to rely on models that emphasise individual behaviour change as the primary mechanism of improvement. At scale, such approaches have shown limited durability and uneven reach, particularly under conditions of structural constraint. These patterns suggest a more fundamental conceptual issue: public mental health is often treated as the aggregate outcome of individual-level change rather than as an emergent property of community systems. This paper develops a systems-based framework that distinguishes three analytically related levels through which public mental health is produced: individual practices, collective capability, and community infrastructure. Collective capability captures whether communities provide the shared conditions that allow individuals to translate resources and intentions into lived well-being in everyday life. Community infrastructure is conceptualised as the design layer through which collective capability is built, stabilised, and unevenly distributed over time, encompassing physical, social, institutional, and temporal arrangements. Situating behaviour change within this broader system architecture helps explain why interventions that appear effective in some contexts often struggle to scale equitably or persist at the population level. Public mental health is further conceptualised as a complex adaptive system characterised by feedback processes, threshold effects, and cumulative advantage and disadvantage. Implications are outlined for research design, measurement and surveillance, and policy, with particular attention to the role of infrastructure and governance in shaping durable and equitable population mental health outcomes.

AB - Public mental health agendas increasingly recognise that mental health outcomes are shaped by social, economic, and environmental conditions, yet much population-level activity continues to rely on models that emphasise individual behaviour change as the primary mechanism of improvement. At scale, such approaches have shown limited durability and uneven reach, particularly under conditions of structural constraint. These patterns suggest a more fundamental conceptual issue: public mental health is often treated as the aggregate outcome of individual-level change rather than as an emergent property of community systems. This paper develops a systems-based framework that distinguishes three analytically related levels through which public mental health is produced: individual practices, collective capability, and community infrastructure. Collective capability captures whether communities provide the shared conditions that allow individuals to translate resources and intentions into lived well-being in everyday life. Community infrastructure is conceptualised as the design layer through which collective capability is built, stabilised, and unevenly distributed over time, encompassing physical, social, institutional, and temporal arrangements. Situating behaviour change within this broader system architecture helps explain why interventions that appear effective in some contexts often struggle to scale equitably or persist at the population level. Public mental health is further conceptualised as a complex adaptive system characterised by feedback processes, threshold effects, and cumulative advantage and disadvantage. Implications are outlined for research design, measurement and surveillance, and policy, with particular attention to the role of infrastructure and governance in shaping durable and equitable population mental health outcomes.

KW - public mental health

KW - complex systems

KW - collective capability

KW - community infrastructure

U2 - 10.1002/mhs2.70054

DO - 10.1002/mhs2.70054

M3 - Article

SN - 2642-3588

VL - 4

JO - Mental Health Science

JF - Mental Health Science

IS - 3

M1 - e70054

ER -