Background: Stunting is the most prevalent form of child undernutrition with current worldwide estimates at 156 million. The majority of these children reside in low- and middle-income countries. When stunting prevails to adulthood, optimal growth potential and economic productivity are minimized. Results: In 2015 there were 98.5 million fewer stunted children under 5 years of age than in 1990. In East Asia and Pacific and South Asia, the stunting prevalence decreased by 24.8 and 25%, respectively. Minimal declines were observed in Latin America and the Caribbean at 12.6%, in the Middle East and North Africa at 12.9%, and in sub-Saharan Africa at 13.4%. But because large populations of children under 5 years of age are distributed disproportionately, decreases in prevalence do not translate to fewer numbers of stunted children globally. In sub-Saharan Africa, the number of stunted children increased by 12.4 million between 1990 and 2015. Conclusions: Adult height is dependent on nutrition-specific or nutrition-sensitive factors. Nutrition-specific factors can be targeted according to their impact at critical points of development and therefore offer multiple windows of opportunity for interventions. To date, many interventions focus on the first 1,000 days, but opportunities may extend into later childhood and adolescence.