Food insecurity is a complex ‘wicked’ problem that results from a range of unstable and uncertain physical, social, cultural, and economic factors that limit access to nutritious food. Globally, 800 million people are undernourished, around 1.9 billion are overweight/obese, and 2 billion have micronutrient deficiency . This, in part, is explained by changes in food production and manufacturing and their impacts on climate change , the retraction in economic climates, increases in food prices, and, in some regions, reduced food availability and access [3,4]. Vulnerable groups include, but are not limited to, migrant populations, Indigenous peoples, elderly populations, pregnant women, those with disabilities, homelessness people, young children, and youth. Poor nutrition during significant periods of growth and development and throughout life impacts long-term health outcomes; increases non-communicable disease prevalence, healthcare costs, and disease burden; and negatively impacts economic and human productivity . This special edition has brought together a variety of articles, some positioned in developing countries where disease burden is high and food insecurity issues impact the growth and development of young children while also negatively affecting adults, specifically their mental and physical health. This issue, Nutrition and Vulnerable Groups, reports novel strategies to address individual, household, and community food security, and draws together quantitative and qualitative research that has attempted to address the challenges of food security while considering the complexity of the problem, the need for locally-driven and scalable solutions, and policy implications.