Diabetes mellitus is a chronic disease of aging that affects more than 20% of people over 65. In older patients with diabetes, comorbidities are highly prevalent and their presence may alter the relative importance, effectiveness, and safety of treatments for diabetes. Randomized controlled trials have shown that intensive glucose control produces microvascular and cardiovascular benefits but typically after extended treatment periods (five to nine years) and with exposure to short term risks such as mortality (in one trial) and hypoglycemia. Decision analysis, health economics, and observational studies have helped to illustrate the importance of acknowledging life expectancy, hypoglycemia, and treatment burden when setting goals in diabetes. Guidelines recommend that physicians individualize the intensity of glucose control and treatments on the basis of the prognosis (for example, three tiers based on comorbidities and functional impairments) and preferences of individual patients. Very few studies have attempted to formally implement and study these concepts in clinical practice. To better meet the treatment needs of older patients with diabetes and comorbidities, more research is needed to determine the risks and benefits of intensifying, maintaining, or de-intensifying treatments in this population. This research effort should extend to the development and study of decision support tools as well as targeted care management.