This manual introduces the Dietary Diversity and Determinants Survey, an adaptable, user-friendly instrument for collecting data on dietary diversity and key determinants of dietary diversity. The survey can be used to conduct situational analyses and baseline surveys; monitor changes in diet due to season, intervention, or shocks; and compare diets of different sub-populations. Survey results provide a snapshot of nutritional trends and gaps, which can inform programmatic decisions for greater nutritional impact in Title II and other food security programs.