Malnutrition and micronutrient deficiencies, often termed “hidden hunger,” are major challenges to global health and food security. Most of the staple crops grown around the globe are typically lacking in important nutrients such as iron (Fe), zinc (Zn), and high-quality protein. Crop bio-fortification has been proven as a viable sustainable and scalable approach to address these deficiencies. Breeding efforts, utilizing traditional methods, marker-assisted selection, and modern tools like CRISPR/Cas9, have successfully enhanced nutrient profiles in staple crops. However, these efforts are often challenged by trade-offs between nutrient content and agronomic traits, limited genetic diversity, and consumer acceptability. The impact of climate change further complicates bio-fortification initiatives, as rising temperatures, erratic rainfall, and soil nutrient depletion adversely affect crop growth and nutrient stability. To combat these challenges, breeding programs are integrating climate resilience into bio-fortification strategies by developing drought-tolerant, heat-resistant, and nutrient-rich crop varieties. Agronomic interventions, such as soil fertility management and foliar nutrient applications, complement breeding efforts to enhance crop nutrition. Additionally, the rediscovery of traditional and indigenous crops, known for their ecological adaptability and nutritional richness, offers a pathway to diversify diets and improve resilience to climate variability. This chapter delves into the strategies in breeding nutrient-rich crops, explores their contribution to global nutrition and food security, and addresses the challenges posed by yield trade-offs, consumer preferences, and climate change. It also highlights future directions, emphasizing the integration of precision agriculture, interdisciplinary research, and policy support to advance bio-fortification and ensure its global adoption.