Type 2 diabetes is the most common form of diabetes, often associated with obesity and genetic predisposition. As Croatia has a high prevalence of obesity, this may result in a further increase in the number of patients with type 2 diabetes. The underlying pathophysiological mechanisms of its development are insulin resistance, increased glucose production in the liver and reduced insulin secretion from the pancreas. The key to prevention and treatment lies in changing lifestyle habits, such as proper nutrition and regular physical activity, which can slow down the progression of the disease and reduce the need for drug therapy. The disease itself, its treatment and failure to achieve good disease control can result in the development of acute and chronic complications. The most common acute complication is actually a consequence of treatment (hypoglycemia), while chronic complications include microvascular and macrovascular complications (retinopathy, nephropathy, polyneuropathy, heart and brain infarction, and peripheral arterial disease, the so-called diabetic foot). The role of the nurse in preventing the development of complications of diabetes is extremely important, and it refers to the implementation of interventions aimed at preventing the disease, improving the quality of life of affected persons, and preventing the development and progression of complications. Understanding diabetes and quality education are prerequisites for proper management of this chronic disease. The paper presents an overview of the causes and symptoms of the disease, diagnostic procedures and preventive and therapeutic measures, as well as possible complications of the disease and its treatment. Special emphasis is placed on the importance of proper nutrition, regular physical activity and self-monitoring of glycemia, all in order to maintain good glucoregulation and reduce the risk of developing complications.