Exploring plant genetic resources is crucial in a time when food security has been a critical topic worldwide due to crop shortages and the impact of climate change. This new book, Plant Genetic Resources for the 21st Century: The OMICS Era, presents the practical advancements in genomics, epigenetics, metabolomics, and phenomics from the point of view of researchers and scientists working in the field of genebanks, genetics resources, and germplasm for enabling plant breeding and adaptation to a changing climate. The book highlights the importance of genebanks as centers of innovation for crop and forage improvement and discusses database solutions for genebanks and germplasm collections. The book first looks at plant genetic resources and their values and goes on to investigate several genomic technologies for plant improvement, conservation, and better adaptation to changing climates. Major crops such as wheat and barley are discussed with genomic approaches for diversity and resilience to drought and other adverse conditions. Other omics techniques discussed include phenomics for the improvement of crop adaptation, metabolomics research for germplasm improvement and adaptation, and more. This volume will be valuable for researchers who are presently working in or with genebanks and genetic resources, primarily for trait or allele discovery and germplasm improvement. Most chapters in the book can also be used as teaching material at the undergraduate and postgraduate levels.