This review examines how forest microrefugia (fine-scale thermal and moisture shelters formed by canopy complexity, deadwood, topography, and snow) protect small mammals from climate extremes in European forests. It synthesizes evidence on the physiological and behavioral sensitivity of rodents and shrews to near-ground abiotic environmental conditions and highlights methods for measuring and modeling microclimatic factors using LiDAR and sensor networks. These findings are integrated into a framework that links structural retention, coarse woody debris, and canopy heterogeneity to microclimate resilience. Despite global advances in microclimate research and the development of new research methods and equipment, empirical data from European forests remain scarce, particularly regarding operative temperature, humidity, and vapor pressure deficit near the ground and within subnivean habitats. By bridging the fields of microclimate physics, small mammal ecology, and silvicultural design, the review identifies the mechanisms and metrics recommended to sustain functional refugia. The synthesis identifies knowledge gaps, standardizes microclimate metrics, and outlines required forest management practices, revitalizing research and inspiring new approaches to small mammal ecology.