Microorganisms are found across diverse ecosystems, including environments that are inhospitable to most life forms. Although yeasts are generally not regarded as resilient as prokaryotic extremophiles, many exhibit remarkable adaptability to harsh conditions such as high salinity, extreme temperatures, desiccation, and highly acidic or alkaline pH levels. Their survival is enabled by a range of physiological and molecular mechanisms, including specialized membrane compositions, efficient DNA repair systems, and unique metabolic pathways. The classification of yeasts as extremophilic or extremotolerant is somewhat subjective and context-dependent, but experimental evidence can support the attribution of certain species to extreme environments. Some yeasts are broad-spectrum survivors, capable of enduring multiple stressors, rather than being narrowly adapted to a single condition. Extreme conditions are present in a wide variety of habitats, often involving multiple stressors simultaneously. Poly-extremophilic environments are more common than previously assumed. In addition to natural extreme habitats, human activity has created numerous artificial extreme environments. Some, like certain foods, are shaped by microbial activity, while others, such as urban habitats, mimic desert-like conditions and are frequently colonized by extremophiles. This chapter provides an overview of extremophilic habitats, the yeasts that thrive in them, and the adaptations that support their survival. Understanding these adaptations not only enhances our knowledge of yeast biology and evolution but also offers promising avenues for biotechnological applications requiring robust microbial systems.