Multiple chemical sensitivity (MCS) and electromagnetic hypersensitivity are disabling conditions hallmarked by adverse reactions to chemicals and electromagnetic frequencies at levels generally considered safe. MCS is underpinned by a vicious cycle of escalating sensitivity initiated by exposure to seven classes of neurotoxicants. Our case study concerns a family sensitized to foods, chemicals and electromagnetic radiation after heavy exposure to phenoxy herbicides and organophosphate pesticides. Also addressed are a number of conditions frequently co-morbid with MCS, which also frequently involve an environmental sensitivity component-which include migraine, rheumatoid arthritis, irritable bowel syndrome, ADHD, hypertension and certain cardiac problems.