This study explored relations among late adolescents' sociomoral reasoning about risk taking, risk stance, and behavior. One-hundred and thirty-two participants (18-20-year-olds) were surveyed about their own risk stance (Avoidant, Opportunistic, Curious, Risk Seeking) and behavior in three realms (Alcohol Use, Drug Use, Reckless Driving), and sociomoral reasoning about hypothetical risk taking in a baseline scenario with no social domain information and a final scenario that highlighted the moral (i.e., harmful consequences for others), conventional (i.e., sociolegal consequences), personal (i.e., personal prerogative), and prudential (i.e., harmful consequences for self) domains bearing on risk taking. The complex relations among sociomoral reasoning about risk taking, risk stance, and behavior are discussed in terms of social domain theory and dual-process theories of risk taking.