This chapter assesses the challenges faced and the mixture of practical, ethical, and legal issues raised by putting biometric technologies into use. Biometrics – measures of life – are measurable human signatures, which include everything from heartbeats, to the shape of ears, and even gait – the way an individual walks. Biometrics could significantly reduce fraud in the distribution of aid, cut the time refugees had to wait to receive benefits, and perhaps also because of this, diminished the chances that some vulnerable members of the refugee host might be radicalised. Biometrics has been effective in ensuring registration throughput and in clearing up the backlog of individuals waiting to be registered. The advent of biometrics offers transformative opportunities for managing major humanitarian crises. On every level, the potential benefits offered by the new technologies carry with them major concerns of security and protection of the information recorded.