Oral and pharyngeal cancers result from a complex interaction between genetic susceptibility and behavioral factors. Improved understanding of the underlying genetic events has led to insights about how oral and pharyngeal cancers develop and suggests promising new treatments. Tobacco and alcohol consumption are associated with most oral and pharyngeal cancers. Dental professionals' efforts to modify their patients' tobacco and alcohol use and to detect oral lesions at an early stage, together with scientific advances, will help reduce the impact of these cancers.