Unprecedented population ageing and rapid urbanisation combine to pose a unique challenge for policymakers– the challenge of ensuring that the greater numbers of older people are not left behind as cities dramatically evolve. As the ability of older people to move about the city and access activities in society are essential to their well-being, there is a large and untapped scope for contributions from the population health sciences to address this challenge. To date, the limited consideration of health and healthy ageing in transport policy has contributed to the high and unsustainable car dependence in Western Europe, North America, and Australia, and the resultant lack of non-driving transport options for older people. This scenario constrains older people’s mobility and well-being, as older people have diverse mobility needs and expectations which can only be met through a range of transportation options. This thesis aims to develop a coherent approach to support older people’s mobility through non-driving transport options by examining population needs and barriers and contextual influences and interventions. To address this aim, four empirical studies were conducted, each responding to one of the four objectives that logically flow from the aim. Driven by a transdisciplinary approach, various methods were used, drawing on both primary and secondary data sources and qualitative and quantitative data types. The thesis identified the specific variables intrinsic to the population to be served that must be considered in efforts to support older people’s mobility, provided evidence of the multifactorial and interactive nature of the influences on older people’s mobility, and illustrated the need for interventions to be holistic and systemic. These four studies contribute guiding principles that constitute the approach that the thesis has set out to develop. As the evidence base from which these guiding principles are developed is grounded in the population health sciences and an appreciation for transport and mobility as a social determinant of health, this thesis has also built a case for a health promotion and, specifically, a healthy public policy approach to efforts to support older people’s mobility. Finally, the thesis has delineated the stakeholders and sectors that need to be in involved in a coherent approach to support older people’s mobility and articulated how they affect each other and why their joint and coordinated contributions are necessary.