Abstract
For more than a century expressions have been approached as bidimensional, static, instantaneous, self-contained, well-defined, and universal signals. These assumptions are starting to be empirically reconsidered: this special section of Emotion Review includes reviews on the physical, social, and cultural dynamics of expressions, and on the complex ways in which, throughout the lifespan, facial behavior and emotion are perceived and categorized by primates’ and humans’ brain. All these advances are certainly paving the way for new exciting approaches to facial behavior more likely to strike an appropriate balance between description and explanation