This white paper, developed in partnership with and funded by The World Bank, examined Call Detail Records (CDRs) and their expanding role in providing insight into human behavior, movements, and social interactions. After providing additional contextual elements (Part 1), the paper summarized current legal frameworks (Part 2), explored structural socio-political parameters and incentives for sharing CDRs (Part 3), proposed guiding ethical principles (Part 4), and discussed operational options and requirements (Part 5).