Half of the world’s wheat crop suffers from heat stress. A 1 °C increase in temperature can reduce wheat yields by as much as 6%. Drought and water availability also are critical, impacting the majority of wheat growing areas of the world. Physiologists and breeders at the International Maize and Wheat Improvement Center (CIMMYT) have been working for decades in sites noted for heat and drought. New technologies, such as high-throughput-phenotyping, are now speeding progress and reducing costs. CIMMYT pre-breeding efforts are introducing new traits from grassy relatives for early vigor, strong roots, lower canopy temperature, stay-green leaves and heads, and pigments to protect photosynthesis.