Across the last century psychology has provided a lot of insight about social-cognitive competence. Recognizing facial expressions, joint attention, discrimination of cues and experiencing empathy are just a few examples of the social skills humans acquire from birth to adolescence. However, how very early brain maturation provides a platform to support the attainment of highly complex social behavior later in development remains poorly understood. Magnetic Resonance Imaging provides a safe means to investigate the typical and atypical maturation of regions of the brain responsible for social cognition in as early as the perinatal period. Here, we first review some technical challenges and advances of using functional magnetic resonance imaging on developing infants to then describe current knowledge on the development of diverse systems associated with social function. We will then explain how these characteristics might differ in infants with genetic or environmental risk factors, who are vulnerable to atypical neurodevelopment. Finally, given the rapid early development of systems necessary for social skills, we propose a new framework to investigate sensitive time windows of development when neural substrates might be more vulnerable to impairment due to a genetic or environmental insult.