Vegetables add diversity, flavour and nutritional quality to diets and provide greater profits and employment per hectare than cereals. On-farm productivity of vegetables in low-income tropical and subtropical countries is generally low and highly variable. Public– private sector networks are crucial for piloting and scaling-up innovations to raise productivity in a safe and sustainable manner – including varietal improvement, pest and disease management, and protected cultivation – and to reduce postharvest losses. The nutritional power of vegetables can be tapped on an intensification gradient, from home gardens aimed at family nutrition to intensive market-oriented vegetable farming to address the growing demand for vegetables at affordable prices. Home garden interventions in Africa and Asia that combined training in vegetable production with communication activities targeting nutrition and health behaviours increased vegetable consumption among rural households vulnerable to micronutrient deficiencies. Less is known about the effectiveness of sack and vertical gardens in urban slums. Training and linking youth with markets for quality vegetables in East Africa showed promise in creating income and employment. Training farmers in off-season tomato production in Bangladesh led to dramatic income improvements but also increased pesticide use. Evidence from Tanzania highlights the market potential of often neglected nutrient-dense indigenous vegetables, such as amaranth and African eggplant. The effect of farm diversification on dietary diversity of farming households seems small, with market access being more important. To tap the nutritional power of vegetables, governments and donors must give greater priority to the vegetable sector through a combination of supply and demand (behaviour change) interventions.