The origins of space ethics are to be found within the space community, with professional philosophers and ethicists joining the discussion more recently. Typical concerns include space mining; risk, disclosure, and justice in space; and iconic topics such as the settlement and terraforming of Mars. These issues may be tackled from different disciplinary perspectives. To convey a constructive sense of the distinctive contribution of ethicists, this chapter highlights the balancing of value considerations, the enhancing of decision-making, the stress-testing of concepts and frameworks, and the importance of ongoing ethical engagement at all stages of space exploration programmes.