The complementary feeding period from 6 to 23 months of age is important for promoting physical and cognitive development, the effects of which will last into adulthood. This UNICEF guidance not only provides information on the benefits of and steps for complementary feeding, but also recognizes the difficulties many face in providing nutritious and sustainable diets for young children. It provides frameworks and interventions for improving diets based on these constraints at the individual, institutional, and policy levels.