Many developing countries lack the capacity and resources to collect and analyze data for evidence-based policy-making. Is big data, which involves large and complex data sets, an opportunity to meet this challenge? Or will it become difficult for developing countries to adopt for solving problems? This project will explore big data's potential to inform development policies in urban planning, infectious diseases, and socio-economic monitoring in Sri Lanka and Bangladesh.Big data and research evidenceSome argue that big data and big data users offer advantages to generate evidence. The availability of information and communication technologies (ICTs) can help reduce efforts to collect large data sets. Mobile phone data, which is one form of big data, has greater reach. It can offer new insights into solving social and economic problems.Transportation, diseases, socio-economic monitoringThe Sri Lankan think tank, Learning Initiatives on Reforms for Network Economies Asia (LIRNEasia), has been exploring the possibility of using big data to inform public policy since 2012. Supported by IDRC, this research focused on transportation planning in urban centres in Colombo to better integrate different parts of cities and suburbs.Building on this pioneering research, LIRNEasia proposes to expand the scope to other development domains. More specifically, the project will explore the use of big data to inform policies in three domains: urban transportation, infectious diseases, and socio-economic monitoring.The project provides an opportunity for LIRNEasia to delve further into linking big data from mobile phone operators to important development domains. In the area of urban transportation, mobile user data could have a significant impact on improving transportation systems in two major cities in South Asia: Colombo and Dhaka. The project may allow both cities to become more efficient in dealing with traffic congestion, pollution, and waste management. Researchers will also explore big data to map the spread of emerging diseases in Sri Lanka. The goal: to improve public health policy.Finally, they will develop methods for mapping poverty through mobile phone transactions such as airtime reloads. This exploratory work will give researchers a better understanding of the patterns of individual economic activities to inform government policy.