The current research program aims to further our knowledge of the unique roles of the sense of smell (olfaction) in several areas of psychology. Olfaction is our evolutionarily oldest sensory system. It is also the least investigated sensory system in human psychology. However, odors play important roles in the everyday life of humans, as reflected in such disparate domains as scent marketing, perfumery, aromatherapy, allergology, food perception, eating disorders, and sexuality. The program is organized according to features that make the sense of smell unique, including the relationship between olfaction and language, olfactory sensations in dreams, the potency of odors to trigger childhood memories and overwhelming emotions, the role of olfaction in food-related behaviors, and the association between olfactory loss and dementia. The research constellation consists of nine internationally established experts in different areas of olfactory research and the collaboration will last for six years. The research proposal is inspired by the notion that although much psychological research interest has been devoted to the study vision and hearing, research on the sense of smell might provide us with important psychological insights.