We explored older adults' experiences of physical activity (PA) and related decision-making processes underlying PA. Twenty Australians (Mage = 73.8 years) participated in semistructured interviews. Data were analyzed using thematic analysis, and identified themes were matched deductively within motivational, volitional, and implicit processes of the integrated behavior change model for PA. Motivational influences such as participants' time orientation toward health and perceptions of what PA should be like were frequently featured in participants' narratives. Volitional processes were also identified, with participants reporting different ways of coping with competing priorities. Physical surroundings and habitual PA were the identified themes within implicit processes. Together, these findings contribute to a better understanding of subjective experiences of older adults regarding PA. They also add to a more contextual understanding of multiple decision-making processes underpinning older adults' PA engagement. Identified concepts may be used in future research and PA interventions targeting older adults.