Oxidative stress refers to a condition caused by an imbalance between the systemic expression of reactive oxygen species (ROS) and the ability of a biological system to quickly detoxify the reactive intermediates or repair the harm. Strand breaks in DNA and base damage are caused by oxidative stress. It can interrupt normal mechanisms of cellular signaling and has been linked to the development of a number of diseases such as cancer, cardiovascular diseases and neurodegenerative diseases. Modulation of oxidative stress is done specifically through the regulation of gene transcription, such as the activation or inhibition of Nrf2. It is regarded as an important strategy for developing new drugs for some of the pathologies, including neoplastic and cardiovascular diseases, that are resistant to other treatments. This book provides significant information to help develop a good understanding of oxidative stress mechanisms and modulation. It presents researches and studies performed by experts across the globe. The extensive content of this book provides the readers with a thorough understanding of this subject.