Pheromones are chemicals emitted by an organism, mediating stereotyped behaviours and/or physiological changes in members of the same species. Pheromones play a key role in mating and social behaviours and are thus often crucial for the survival of the species. This review describes the highly sophisticated structures and mechanisms underlying pheromone reception and transduction in both mammals and insects, from a comparative point of view. Recent advances were gained in the field of pheromone communication by multidisciplinary approaches combining immunocytochemical, bio-chemical, electrophysiological and molecular genetical investigations. Pheromone reception and transduction mechanisms present striking similarities between mammals and insects. They share a common design in their chemosensory systems, with a similar cellular organization, and a conserved logic in pheromone coding. Both in mammals and in insects, the detection of pheromonal cues involves pheromone-binding proteins, G-protein coupled receptors as pheromone receptors, a transduction pathway with a central role of calcium and a first processing of the pheromonal signals in glomerular structures. Rather than homologous mechanisms, the observed similarities in pheromone reception and transduction processes in mammals and insects may result from convergent adaptations that could originate from common selective pressures.