Basic and selected functional properties of simple sugars, sugar alcohols, corn and maple syrups, honey, and high-fructose corn syrups are discussed. Properties that relate to sweetness and properties that play roles in component interaction as a basis for product formulation are described. The implications of such functionality are illustrated for the development of low-energy foods and for the microwave heating of foods. Among the properties discussed are solubility, hygroscopicity, crystallinity, and viscosity. Interrelations among water mobility, water activity, and hydration of proteins, lipids, and carbohydrates are described in the context of food formulation. Application of polymer chemistry principles to explain functional properties of amorphous molecules is reviewed.