Many aspects of our everyday cognition are concerned with the representation of self and others. How are we able to generate intentional actions and distinguish that from external stimuli? What is the role of inner body signals in the emergence of self-consciousness and perception of social signals? What are the bases of intersubjectivity and empathy? How can we represent the beliefs and intentions of others independently of the physical reality (mentalization)? Novel data from neuropsychology and functional neuroimaging demonstrate that functional connections between prefrontal cortex and sensory areas are critical in the discrimination of internally generated actions from external events. Specific brain areas, such as the amygdala and the posterior superior temporal cortex, participate in the processing of social signals, whereas the dorsomedial prefrontal cortex is crucial for mentalization. Finally, mirror neurons, which show responses during intentional actions and observation of others performing those actions, exist in many brain areas and establish the foundations of intersubjectivity and the biological roots of mimetic culture. Some cortical areas containing mirror neurons are also related to language processing. Discovering brain mechanisms of social cognition may change fundamental views about the philosophy of mind and may provide a new possibility to understand psychiatric disorders.