Complementary and alternative medicine (CAM) use has increased in popularity in recent years and herbal therapy alone is now a billion dollar market. For centuries herbs have been used as food and for medicinal purposes. Various herbs have been identified as possessing anti-inflammatory and antioxidative properties, and they are currently being used to treat inflammatory disorders as well as those caused by reactive oxygen species (ROS). Asthma, Alzheimer's disease, inflammatory bowel disease (IBD), rheumatoid arthritis (RA), and atherogenesis are all disorders where inflammation and ROS are involved in their pathogenesis. This review examines the pathogenesis of the above mentioned ROS-mediated inflammatory disorders, as well as discusses the antioxidant and anti-inflammatory mechanisms of various herbs and the clinical trials where herbs have been used to treat these disorders.