The public health problem selected for this study is T2D, a growing non-communicable disease that significantly contributes to morbidity, mortality, and reduced quality of life worldwide. This issue is particularly relevant in small island settings such as St Helena Island south of Atlantic , where geographic isolation, limited healthcare resources, and increasing exposure to lifestyle-related risk factors exacerbate its impact. Diabetes is a chronic condition requiring ongoing self-management, making it important to understand how individuals navigate care within this unique context. The study focuses specifically on the barriers and facilitators influencing effective diabetes management among adults, including medication adherence, lifestyle behaviors, access to healthcare services, and individual knowledge and beliefs. Consideration has been given to the extent of the problem, which is rising globally and disproportionately affecting remote populations, as well as its causes, such as dietary changes, sedentary lifestyles, and systemic healthcare limitations. Potential solutions include strengthening primary care, improving access to medication and education, and implementing culturally appropriate interventions. This aspect has been prioritised because improving diabetes management can lead to better health outcomes and more efficient use of limited healthcare resources. A review of existing literature indicates that challenges such as healthcare access, cultural influences, and resource constraints are common in similar settings, reinforcing the need for context-specific research. Therefore, a focused research question guiding this study is: “What are the key barriers and facilitators influencing effective diabetes self-management among adults in small island settings, particularly in Saint Helena, and how do these differ between individuals with good and poor glycaemic control?”