Cassava is a crucial crop, particularly in tropical and subtropical regions, where it serves as a primary source of carbohydrates and contributes significantly to food security. This chapter focuses on the conservation, characterization, evaluation, and utilization of cassava plant genetic resources, which are essential for its sustainable cultivation and improvement. Originating in South America, cassava has spread globally, particularly in Africa, Asia, and Latin America, due to its adaptability to diverse environments. Cassava genetic diversity, including wild relatives, landraces, and improved varieties, provides valuable traits such as disease resistance, drought tolerance, and high yield potential. The chapter discusses methods for conserving and characterizing these genetic resources, including the development of core collections and the use of molecular markers, such as SSR, SNP, and ISSR. These tools enable the identification of key traits and provide insights into cassava phylogeny and evolution. Efforts to improve cassava through breeding programs have focused on addressing production constraints like pests, diseases, and environmental stress. Varieties such as Sree Harsha, Hope, and Nanzhi 199 have been developed with enhanced traits, including higher starch content, resistance to cassava mosaic disease and cassava brown streak disease, and improved drought tolerance. Nutritional improvements, such as reducing cyanogenic compounds and enhancing provitamin A content, are also important goals. The future of cassava research lies in the integration of genomics, biotechnology, and gene editing techniques like CRISPR-Cas9 to accelerate trait improvements. These advances will help address ongoing challenges such as climate change, pests, and disease, ensuring the crop’s continued importance in global agriculture. This chapter highlights the critical role of cassava PGR in fostering food security, agricultural resilience, and sustainable development.