Due to rapid population growth, climate change, and decreasing natural resources, growing sufficient crops with high productivity, resistance to abiotic and biotic stresses, and other attractive traits is a major challenge. Conventional breeding methods require time-consuming genetic crosses between different parents for multiple generations. By contrast, plant transformation is defined as the insertion of DNA from any organism into the genome of a plant species, and it is considered to be a powerful tool in plant breeding. This book aims to provide professional state-of-the-art information for basic and applied scientists and plant breeders, focusing on key crop plants. Papers related to the principle and application of Agrobacterium-mediated transformation, step-by-step protocols of DNA delivery to the important crop Brassica oleracea and higher-plant chloroplasts, current progress and prospects of virus-induced gene silencing (VIGS) in higher plants, improvement of grapevine through biotechnology, and public concern of biosafety issues regarding genetically modified organisms (GMOs) are all included in this book. It should be useful for students, breeders, and researchers in the field of transgenic crops around the world.