In this study, we first briefly review the basic properties of a particular set of neurons that discharge both when the individuals execute a specific action and when they observe another individual doing a similar action. These neurons are called mirror neurons. We then show that mirror neurons mediate our capacity to understand actions done by others. In the second part of the study we discuss the role of the mirror mechanism in intention understanding. We conclude with a review of recent data suggesting that a deficit in the mirror neuron mechanism may underlie some aspects of autism.