Diabetes mellitus is a chronic disease characterized by a deficient carbohydrate metabolism. The most prevalent types are type 1 and type 2 diabetes mellitus, with type 2 diabetes mellitus representing 90% of cases. It is estimated that in the Latin American region, 32.5 million adults live with diabetes, which represents 9.5% of the population. People with diabetes mellitus have a higher risk of premature mortality, developing cardiovascular disease and microvascular and macrovascular complications, and experiencing a decrease in their quality of life. The treatment of diabetes mellitus is complex and multidimensional and is characterized by adherence rates that fluctuate between 20% and 80%. Various factors act as barriers or facilitators of treatment adherence, such as psychological stress, interpersonal relationships, and the doctor–patient relationship, and successful interventions have been carried out in Latin America to address each of these aspects individually. However, adherence is a complex and multidetermined phenomenon, and it is therefore relevant to adopt an integrative perspective that considers the possible interactions between these variables and allows for a specific understanding of the phenomenon of adherence to diabetes mellitus treatment.