Plants are continuously exposed to a wide range of changing environmental and climatic stresses, including drought, salinity, extreme temperatures, nutrient imbalances, greenhouse gases, heavy metal toxicity, and pathogen attacks. Unlike animals, plants are immobile and cannot escape these adverse conditions, making adaptive resilience and physiological responses critical for their survival and growth. Recent advances in plant science, particularly in the field of epigenetics, have revealed key mechanisms that modulate gene expression without altering the underlying DNA sequence. Epigenetic processes, including DNA methylation, histone modifications, and small RNA-mediated regulation, play significant roles in modulating plant responses to environmental and climatic stressors. These mechanisms contribute to stress memory, enabling plants to “remember” previous stress events and exhibit enhanced resilience when exposed to similar conditions in the future. This chapter explores the pivotal role of epigenetic modifications in plant adaptive resilience, with a focus on stress-induced epigenetic changes, their reversibility, and heritability. Understanding these epigenetic processes holds immense potential to transform plant breeding and improvement strategies, offering sustainable solutions for agriculture under a changing climate. Furthermore, leveraging epigenetic knowledge can help in developing stress-tolerant crop varieties, thereby contributing to food security and achieving the Sustainable Development Goals.