Without adaptation solutions now, millions of smallholder farmers will be unprepared for the severe consequences of increased temperature, drought, flooding, and other climate extremes. Building Systemic Resilience Against Climate Variability and Extremes, or ClimBeR, is a CGIAR Research Initiative that will address this challenge as part of CGIAR’s new research portfolio that will deliver science and innovation to transform food, land, and water systems in a climate crisis. This publication provides an overview of the Initiative.