Climate change is likely to increase climate variability especially in temperatures and rainfall leading to droughts, floods, land degradations, genetic erosion of landraces and crop wild relatives (CWR), and outbreak of insect-pest and pathogens, affecting crop productivity and food security. The genetic variation required to overcome these changes is available in germplasm collections. Worldwide ~7.4 million germplasm accessions (44% landraces, 17% CWR) are preserved in ~1750 genebanks and ~2500 botanical gardens. ICRISAT genebank conserves >119700 germplasm accessions of chickpea, pigeonpea, groundnut, sorghum, pearl millet and six small millets, and have supplied 1.37 million seed sample to scientists in 144 countries in the last 37 years. However, there has been exiguous use of these resources in crop breeding resulting narrow genetic base of improved cultivars making them vulnerable to biotic and abiotic stresses. To enhance the use of germplasm in crop improvement ICRISAT scientists have developed and shared the mini core collections of chickpea, pigeonpea, groundnut, sorghum, pearl millet and finger millet with partners in NARS and ARIs. Using mini core collections, scientists at ICRISAT and partner institutes have identified new sources of variation for resistance to biotic and abiotic stresses and agronomic traits that are needed to overcome the challenges of climate change. CWR have provided not only sources of variation for stress tolerance but also for enhancing agronomic traits. The use of these new trait-specific variations in crop improvement will result in high yielding, broad-based cultivars suitable to overcome the challenges of the climate change.