Nutrition is an important determinant of health in persons over the age of 65. Malnutrition in the elderly is often underdiagnosed. Careful nutritional assessment is necessary for both the successful diagnosis and development of comprehensive treatment plans for malnutrition in this population. The purpose of this article is to provide clinicians with an educational overview of this essential but often underecognized aspect of geriatric assessment. This article will review some common issues in nutrition for the elderly in both hospital and community settings. The complexity and impact of multiple comorbidities on the successful nutritional assessment of elderly patients is highlighted by using case scenarios to discuss nutritional issues common to elderly patients and nutritional assessment tools. Three case studies provide some context for an overview of these issues, which include the physiology of aging, weight loss, protein undernutrition, impaired cognition, malnutrition during hospitalization, screening procedures, and general dietary recommendations for patients 65 years of age and older.