The remainder of this report is organized in four chapters. Chapter 2 reviews exposure factors important for assessing health risks associated with beryllium. It includes a review of the exposure assumptions that underlie existing exposure standards, consideration of exposures in natural and anthropogenic settings, and an examination of how physiochemical characteristics and particle sizes are associated with risk of disease. Chapter 3 provides an overview of the scientific literature on beryllium sensitization and CBD, including what is known about pathogenesis, mode of action, and genetic susceptibility. Chapter 4 focuses on the evidence of beryllium’s carcinogenic potential. Other health end points, such as reproductive and developmental effects, are reviewed in Chapter 5.