Humans are an exquisitely social species. Our survival critically depends on our ability to thrive in complex social situations. In my talk I will present evidence that, in our nervous system, there is a specific neural mechanism (mirror neuron mechanism) that allows us to understand the actions done by others, their intentions, and emotions. The mirror mechanism produces, in our brain, motor representations that reflect actions and emotions observed in others. Because we know the outcome of our motor representations, we have, through the mirror mechanism, an immediate, direct knowledge of what the others are doing and feeling. I will conclude showing some implications of these finding for understanding some neurological and psychiatric disturbances.