Sick building syndrome. "Sick building syndrome" (SBS) is one of the more colorful terms describing an increasingly common pattern of symptoms found among workers in modern office buildings. Core symptoms include lethargy, mucous membrane irritation, headache, eye irritation, and dry skin. To prompt a diagnosis of SBS, these otherwise common symptoms must be "excessively" reported and primarily "work-related." The World Health Organization now estimates that 30% of new or remodeled office buildings show signs of SBS, and that between 10% and 30% of the occupants of these buildings are affected by SBS. Despite such figures, SBS remains poorly researched and even more poorly understood. The following review provides the clinician an overview of SBS that will allow a more accurate differential diagnosis and will help to prevent the widespread suffering that can accrue when SBS is not quickly recognized. 