On February 10, 2021, Data for Impact (D4I) held a webinar in a series sharing lessons learned and practical suggestions on using routine and other existing data for evaluation and research. This one-hour webinar was led by D4I’s Emily Weaver, PhD, and focused on using multiple secondary data sources in evaluation and discuss related work in Nigeria. The increased availability of data from multiple sources in low- and middle-income countries in recent years, combined with advances in data science, have stimulated an increased interest in using existing data in innovative ways to bring new insights to population, health, and nutrition problems. At the same time, linking data from different sources provides both opportunities and challenges. This webinar provided lessons learned from experiences linking the Nigeria Demographic and Health Survey with the Nigeria Living Standards Measurement Survey — Integrated Survey on Agriculture to assess health outcomes. Watch the webinar recording. Speaker Emily Weaver, PhD, has worked for 16 years in research and evaluation of public health programs with expertise in reproductive, maternal, newborn and child health (RMNCH). At Data for Impact, Dr. Weaver leads evaluations in sub-Saharan Africa and Asia for programs focused on RMNCH, nutrition, and HIV.